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Form Field

Form Field (15)

This article demonstrates how to remove a particular form field and all of the form fields from an existing PDF document using Spire.PDF.

The below sample document contains some text and five different kinds of form fields:

Remove/Delete Form Fields from PDF in C#

Remove a particular form field

We can remove a particular form field by calling the PdfFieldCollection.Remove method. To remove the form field by index, call the PdfFieldCollection.RemoveAt method and pass the corresponding index of the form field as the argument.

using Spire.Pdf;
using Spire.Pdf.Fields;
using Spire.Pdf.Widget;


namespace RemoveSpecifiedFormfield
{
    class Program
    {
        static void Main(string[] args)
        {
            //Create PdfDocument instance
            PdfDocument pdf = new PdfDocument();

            //Load PDF file
            pdf.LoadFromFile(@"Input.pdf");

            //Get form fields
            PdfFormWidget formWidget = pdf.Form as PdfFormWidget;

            //Get and remove the first form field
            PdfField textbox = formWidget.FieldsWidget.List[0] as PdfTextBoxFieldWidget;
            formWidget.FieldsWidget.Remove(textbox);

            //Get and remove the first form field using its name
            //PdfField field = formWidget.FieldsWidget["Text1"];
            //formWidget.FieldsWidget.Remove(field);

            //Remove the form field at index 0
            //formWidget.FieldsWidget.RemoveAt(0);

            pdf.SaveToFile("DeleteParticularField.pdf");
        }

    }
}

Remove/Delete Form Fields from PDF in C#

Remove all of the form fields

To remove all of the form fields, first we need to traverse the form fields and then remove them one by one.

using Spire.Pdf;
using Spire.Pdf.Fields;
using Spire.Pdf.Widget;


namespace RemoveSpecifiedFormfield
{
    class Program
    {
        static void Main(string[] args)
        {
            //Create PdfDocument instance
            PdfDocument pdf = new PdfDocument();

            //Load PDF file
            pdf.LoadFromFile(@"Input.pdf");

            //Get form fields
            PdfFormWidget formWidget = pdf.Form as PdfFormWidget;

            //Remove all of the form fields
            for (int i = formWidget.FieldsWidget.List.Count - 1; i >= 0; i--)
            {
                PdfField field = formWidget.FieldsWidget.List[i] as PdfField;
                formWidget.FieldsWidget.Remove(field);
            }

            pdf.SaveToFile("DeleteAllFields.pdf");
        }

    }
}

Remove/Delete Form Fields from PDF in C#

In PDF, buttons can be assigned icon appearances and each button can have as many as three appearances: Normal, Rollover, and Click. With Spire.PDF, not only can we assign icons to buttons, but also we can change the icons of buttons. In this article, we’re going to show you how to assign an icon to a button and set icon layout using Spire.PDF and C#. As for changing icons, please refer How to change the image on button field in C#.

Code Snippets:

Step 1: Create a PDF document and add a page to it.

PdfDocument doc = new PdfDocument();
PdfPageBase page = doc.Pages.Add();

Step 2: Create a button field.

PdfButtonField btn = new PdfButtonField(page, "button1");
btn.Bounds = new RectangleF(0, 50, 120, 100);

Step 3: Set button layout.

btn.HighlightMode = PdfHighlightMode.Push;
btn.LayoutMode = PdfButtonLayoutMode.CaptionOverlayIcon;
//Set text and icon for Normal appearance
btn.Text = "Normal Text";
btn.Icon = PdfImage.FromFile("Image.png");
//Set text and icon for Click appearance (Can only be set when highlight mode is Push)
btn.AlternateText = "Alternate Text";
btn.AlternateIcon = PdfImage.FromFile("Sunflower.jpg");
//Set text and icon for Rollover appearance (Can only be set when highlight mode is Push)
btn.RolloverText = "Rollover Text";
btn.RolloverIcon = PdfImage.FromFile("PinkRoses.jpg");

Step 4: Set icon layout.

btn.IconLayout.Spaces = new float[] { 0.5f, 0.5f };
btn.IconLayout.ScaleMode = PdfButtonIconScaleMode.Proportional;
btn.IconLayout.ScaleReason = PdfButtonIconScaleReason.Always;
btn.IconLayout.IsFitBounds = false;

Step 5: Add the button to the document.

doc.Form.Fields.Add(btn);

Step 6: Save the document.

doc.SaveToFile("AddIcon.pdf");

The resultant document looks as follows:

Assign an Icon to a PDF Button Field and Set Icon Layout in C#

Full code:

using System.Drawing;
using Spire.Pdf;
using Spire.Pdf.Fields;
using Spire.Pdf.Graphics;

namespace Add_Icon_to_PDF_Button_Field
{
    class Program
    {
        static void Main(string[] args)
        {   
            //Create a PDF document       
            PdfDocument doc = new PdfDocument();
            PdfPageBase page = doc.Pages.Add();

            //Create a Button
            PdfButtonField btn = new PdfButtonField(page, "button1");
            btn.Bounds = new RectangleF(0, 50, 120, 100);
            btn.HighlightMode = PdfHighlightMode.Push;
            btn.LayoutMode = PdfButtonLayoutMode.CaptionOverlayIcon;
            //Set text and icon for Normal appearance
            btn.Text = "Normal Text";
            btn.Icon = PdfImage.FromFile("Image.png");
            //Set text and icon for Click appearance (Can only be set when highlight mode is Push)
            btn.AlternateText = "Alternate Text";
            btn.AlternateIcon = PdfImage.FromFile("Sunflower.jpg");
            //Set text and icon for Rollover appearance (Can only be set when highlight mode is Push)
            btn.RolloverText = "Rollover Text";
            btn.RolloverIcon = PdfImage.FromFile("PinkRoses.jpg");

            //Set icon layout
            btn.IconLayout.Spaces = new float[] { 0.5f, 0.5f };
            btn.IconLayout.ScaleMode = PdfButtonIconScaleMode.Proportional;
            btn.IconLayout.ScaleReason = PdfButtonIconScaleReason.Always;
            btn.IconLayout.IsFitBounds = false;

            //Add the button to the document
            doc.Form.Fields.Add(btn);

            //Save the document
            doc.SaveToFile("AddIcon.pdf");            
        }
    }
}

When we operate the ComboBox field and ListBox field on PDF files, we can set the options for Dropdown Properties. This article will focus on how you how to set "Commit selected value immediately" property for ComboBox field and ListBox field. We will divide into two parts for how to set the property of "Commit selected value immediately", one is for the existing field on PDF and the other is for the new field added to the PDF file.

The following code is for how to set "Commit selected value immediately" property for the existing ListBox field on PDF:

//create a PDF document and load the document from file
 PdfDocument pdf = new PdfDocument();
 pdf.LoadFromFile("FormField.pdf");

 //get the existing form
 PdfFormWidget fw = pdf.Form as PdfFormWidget;

 //get the ListBox field and set the field of CommitOnSelChange property as true
 if (fw != null)
 {
     for (int i = 0; i < fw.FieldsWidget.Count; i++)
     {
         if (fw.FieldsWidget[i] != null)
         {
             if (fw.FieldsWidget[i] is PdfListBoxWidgetFieldWidget)
             {

                 (fw.FieldsWidget[i] as PdfListBoxWidgetFieldWidget).CommitOnSelChange = true;
             }
         }
     }
 }
 pdf.SaveToFile("Result.pdf");

Set

The following code is for how to set the property of "Commit selected value immediately" for ComboBox field when we add a new ComboBox field on PDF:

using (PdfDocument pdf = new PdfDocument())
{
    PdfPageBase page = pdf.Pages.Add();
    
     //add a new ComboBox Field and add data to it
PdfComboBoxField combo = new PdfComboBoxField(page, "ComboBox");
    combo.Bounds = new RectangleF(20, 20,60, 20);
    PdfListFieldItem item1 = new PdfListFieldItem("First", "1");
    PdfListFieldItem item2 = new PdfListFieldItem("Second", "2");
    combo.Items.Add(item1);
    combo.Items.Add(item2);

//set the field of CommitOnSelChange property as true
    combo.CommitOnSelChange = true;

    pdf.Form.Fields.Add(combo);
    pdf.SaveToFile("Result2.Pdf");
}

Set

Working with FDF and XFDF Files

2017-03-21 07:34:26 Written by support iceblue

Spire.PDF allows importing FDF, XFDF files to PDF forms as well as exporting PDF forms data to FDF, XFDF files.

The below code examples illustrate how to implement the above features using Spire.PDF.

Importing FDF/ XFDF to PDF

To import FDF/XFDF file to PDF, we can use the ImportData method in the PdfFormWidget class:

using Spire.Pdf;
using Spire.Pdf.Widget;


namespace ImportingFDFOrXFDFtoPDF
{
    class Program
    {
        static void Main(string []args)
        {
            //Load the PDF document
            PdfDocument document = new PdfDocument("Import.pdf");

            //Load the existing forms 
            PdfFormWidget loadedForm = document.Form as PdfFormWidget;

            //Import FDF to PDF
            loadedForm.ImportData("ImportFDF.fdf", DataFormat.Fdf);

            //Import XFDF to PDF
            //loadedForm.ImportData("ImportXFDF.xfdf", DataFormat.XFdf);

            //Save the document
            document.SaveToFile("Output.pdf");

            //Close the document
            document.Close();
        }
    }
}

Exporting PDF Forms Data to FDF/XFDF

To export PDF forms data to FDF/XFDF file, we can use the ExportData method in the PdfFormWidget class:

using Spire.Pdf;
using Spire.Pdf.Fields;
using Spire.Pdf.Widget;


namespace ExportingPDFFormsDatatoFDFAndXFDF
{
    class Program
    {
        static void Main(string[] args)
        {
            // Load the PDF document
            PdfDocument document = new PdfDocument("Export.pdf");

            //Load the existing forms 
            PdfFormWidget loadedForm = document.Form as PdfFormWidget;

            //Export the first form to FDF
            PdfField field = loadedForm.FieldsWidget.List[0] as PdfField;
            loadedForm.ExportData("ExportFDF.fdf", DataFormat.Fdf, field.Name);

            //Export the first form to XFDF
            //loadedForm.ExportData("ExportXFDF.xfdf", DataFormat.XFdf, field.Name);

            //Close the document
            document.Close();
        }
    }
}

Flattening form fields is an efficient way to prevent others from modifying or deleting the form field contents in PDF. After flattening, the editing or filling capability of the form fields will be removed and their contents will appear as regular text. In this article, you will learn how to flatten form fields in a PDF document in C# and VB.NET using Spire.PDF for .NET.

Install Spire.PDF for .NET

To begin with, you need to add the DLL files included in the Spire.PDF for.NET package as references in your .NET project. The DLLs files can be either downloaded from this link or installed via NuGet.

PM> Install-Package Spire.PDF

Flatten a Specific Form Field in PDF in C# and VB.NET

The following are the steps to flatten a specific form field in a PDF document using Spire.PDF for .NET:

  • Initialize an instance of PdfDocument class.
  • Load a PDF document using PdfDocument.LoadFromFile() method.
  • Get the form widget collection from the document.
  • Get a specific form field from the widget collection by its name or index through PdfFormWidget.FieldsWidget["fieldName"] property or PdfFormWidget.FieldsWidget.List[fieldIndex] property.
  • Flatten the form field through PdfField.Flatten property.
  • Save the result document using PdfDocument.SaveToFile() method.
  • C#
  • VB.NET
using Spire.Pdf;
using Spire.Pdf.Fields;
using Spire.Pdf.Widget;

namespace FlattenSpecificFormField
{
    class Program
    {
        static void Main(string[] args)
        {
            //Create a PdfDocument instance
            PdfDocument pdf = new PdfDocument();
            //Load a PDF document
            pdf.LoadFromFile("Form.pdf");

            //Get the form widget collection
            PdfFormWidget formWidget = (PdfFormWidget)pdf.Form;
            //Get a specific form field by its name
            PdfField form = formWidget.FieldsWidget["Address"];
            //Get a specific form field by its index
            //PdfField form = formWidget.FieldsWidget.List[2] as PdfField;
            //Flatten the form
            form.Flatten = true;

            //Save the result document
            pdf.SaveToFile("FlattenSpecific.pdf");
        }
    }
}

C#/VB.NET:  Flatten Form Fields in PDF

Flatten All Form Fields in PDF in C# and VB.NET

The following are the steps to flatten all the form fields in a PDF document using Spire.PDF for .NET:

  • Initialize an instance of PdfDocument class.
  • Load a PDF document using PdfDocument.LoadFromFile() method.
  • Flatten all the form fields in the document through PdfDocument.Form.IsFlatten property.
  • Save the result document using PdfDocument.SaveToFile() method.
  • C#
  • VB.NET
using Spire.Pdf;

namespace FlattenAllFormFields
{
    class Program
    {
        static void Main(string[] args)
        {
            //Create a PdfDocument instance
            PdfDocument pdf = new PdfDocument();
            //Load a PDF document
            pdf.LoadFromFile("Form.pdf");

            //Flatten all the forms in the document
            pdf.Form.IsFlatten = true;

            //Save the result document
            pdf.SaveToFile("FlattenAll.pdf");
        }
    }
}

C#/VB.NET:  Flatten Form Fields in PDF

Apply for a Temporary License

If you'd like to remove the evaluation message from the generated documents, or to get rid of the function limitations, please request a 30-day trial license for yourself.

XFA forms are XML-based forms created by Adobe's LiveCycle Designer tool, which offer enhanced features over the old AcroForms, like changeable text fields and support for running JavaScript. Spire.PDF supports to access the XFA forms in an existing PDF file and fill the fields with data.

Step 1: Initialize an instance of PdfDocument class and load a sample PDF file containing dynamic XFA forms.

PdfDocument doc = new PdfDocument();
doc.LoadFromFile("DynamicXFA.pdf");

Step 2: Get all form widgets from the document.

PdfFormWidget formWidget = doc.Form as PdfFormWidget;

Step 3: Get a list of XFA Fields.

List<XfaField> xfafields = formWidget.XFAForm.XfaFields;

Step 4: Traverse each XfaField in the list and judge if it is an XfaTextField, if yes, convert the type of XfaField as an XfaTextField and then assign value to the field based on the field name.

foreach (XfaField xfaField in xfaFields)
{
    if (xfaField is XfaTextField)
    {
        XfaTextField xf = xfaField as XfaTextField;
        switch (xfaField.Name)
        {
            case "EmployeeName":
                xf.Value = "Gary";
                break;
            case "Address":
                xf.Value = "Chengdu, China";
                break;
            case "StateProv":
                xf.Value = "Sichuan Province";
                break;
            case "ZipCode":
                xf.Value = "610093";
                break;
            case "SSNumber":
                xf.Value = "000-00-0000";
                break;
            case "HomePhone":
                xf.Value = "86-028-81705109";
                break;
            case "CellPhone":
                xf.Value = "123456789";
                break;
            case "Comments":
                xf.Value = "This demo shows how to fill XFA forms using Spire.PDF";
                break;
            default:
                break;
        }
    }
}

Step 5: Save the file.

doc.SaveToFile("FillXfaField.pdf",FileFormat.PDF);

Output:

How to Fill XFA Form Fields in C#, VB.NET

Full Code:

[C#]
using Spire.Pdf;
using Spire.Pdf.Widget;
using System.Collections.Generic;


namespace FillXFAFormFields
{
    class Program
    {
        private static IEnumerable xfaFields;
        static void Main(string []args)
        {
            PdfDocument doc = new PdfDocument();
            doc.LoadFromFile("DynamicXFA.pdf");

            PdfFormWidget formWidget = doc.Form as PdfFormWidget;
            List xfafields = formWidget.XFAForm.XfaFields;
            foreach (XfaField xfaField in xfaFields)
            {
                if (xfaField is XfaTextField)
                {
                    XfaTextField xf = xfaField as XfaTextField;
                    switch (xfaField.Name)
                    {
                        case "EmployeeName":
                            xf.Value = "Gary";
                            break;
                        case "Address":
                            xf.Value = "Chengdu, China";
                            break;
                        case "StateProv":
                            xf.Value = "Sichuan Province";
                            break;
                        case "ZipCode":
                            xf.Value = "610093";
                            break;
                        case "SSNumber":
                            xf.Value = "000-00-0000";
                            break;
                        case "HomePhone":
                            xf.Value = "86-028-81705109";
                            break;
                        case "CellPhone":
                            xf.Value = "123456789";
                            break;
                        case "Comments":
                            xf.Value = "This demo shows how to fill XFA forms using Spire.PDF";
                            break;
                        default:
                            break;
                    }
                }
            }
            doc.SaveToFile("FillXfaField.pdf", FileFormat.PDF);
        }
    }
}
[VB.NET]
Imports Spire.Pdf
Imports Spire.Pdf.Widget
Imports System.Collections.Generic


Namespace FillXFAFormFields
	Class Program
		Private Shared xfaFields As IEnumerable(Of XfaField)
		Private Shared Sub Main(args As String())
			Dim doc As New PdfDocument()
			doc.LoadFromFile("DynamicXFA.pdf")

			Dim formWidget As PdfFormWidget = TryCast(doc.Form, PdfFormWidget)
			Dim xfafields__1 As List(Of XfaField) = formWidget.XFAForm.XfaFields
			For Each xfaField As XfaField In xfaFields
				If TypeOf xfaField Is XfaTextField Then
					Dim xf As XfaTextField = TryCast(xfaField, XfaTextField)
					Select Case xfaField.Name
						Case "EmployeeName"
							xf.Value = "Gary"
							Exit Select
						Case "Address"
							xf.Value = "Chengdu, China"
							Exit Select
						Case "StateProv"
							xf.Value = "Sichuan Province"
							Exit Select
						Case "ZipCode"
							xf.Value = "610093"
							Exit Select
						Case "SSNumber"
							xf.Value = "000-00-0000"
							Exit Select
						Case "HomePhone"
							xf.Value = "86-028-81705109"
							Exit Select
						Case "CellPhone"
							xf.Value = "123456789"
							Exit Select
						Case "Comments"
							xf.Value = "This demo shows how to fill XFA forms using Spire.PDF"
							Exit Select
						Case Else
							Exit Select
					End Select
				End If
			Next
			doc.SaveToFile("FillXfaField.pdf", FileFormat.PDF)
		End Sub
	End Class
End Namespace

Required fields force the user to fill in the selected form field. If the user attempts to submit the form while a required field is blank, an error message appears and the empty required form field is highlighted.

Using Spire.PDF, we're able to enforce a form field as "Required" or determine which fields are required in an existing PDF document. This article mainly introduce how to detect the required form fields in C# and VB.NET.

Code Snippet:

Step 1: Initialize an instance of PdfDocument class and load a sample PDF file that contains some form fields.

PdfDocument doc = new PdfDocument();
doc.LoadFromFile(@"C: \Users\Administrator\Desktop\PdfFormExample.pdf");

Step 2: Get all form widgets from the PDF document.

PdfFormWidget formWidget = doc.Form as PdfFormWidget;

Step 3: Traverse the form widgets to find the form field that is required and print all results on console.

for (int i = 0; i < formWidget.FieldsWidget.List.Count; i++)
{
    PdfField field = formWidget.FieldsWidget.List[i] as PdfField;
    string fieldName = field.Name;
    bool isRequired = field.Required;
    if (isRequired)
    {
        Console.WriteLine(fieldName + " is required.");
    }
}

Output:

How to Detect the Required Form Field in PDF in C#, VB.NET

Full Code:

[C#]
using Spire.Pdf;
using Spire.Pdf.Fields;
using Spire.Pdf.Widget;
using System;

namespace Detect
{
    class Program
    {
        static void Main(string []args)
        {
            PdfDocument doc = new PdfDocument();
            doc.LoadFromFile(@"C: \Users\Administrator\Desktop\PdfFormExample.pdf");

            PdfFormWidget formWidget = doc.Form as PdfFormWidget;
            for (int i = 0; i < formWidget.FieldsWidget.List.Count; i++)
            {
                PdfField field = formWidget.FieldsWidget.List[i] as PdfField;
                string fieldName = field.Name;
                bool isRequired = field.Required;
                if (isRequired)
                {
                    Console.WriteLine(fieldName + " is required.");
                }
            }
            Console.ReadKey();
        }
    }
}
[VB.NET]
Imports Spire.Pdf
Imports Spire.Pdf.Fields
Imports Spire.Pdf.Widget

Namespace Detect
	Class Program
		Private Shared Sub Main(args As String())
			Dim doc As New PdfDocument()
			doc.LoadFromFile("C: \Users\Administrator\Desktop\PdfFormExample.pdf")

			Dim formWidget As PdfFormWidget = TryCast(doc.Form, PdfFormWidget)
			For i As Integer = 0 To formWidget.FieldsWidget.List.Count - 1
				Dim field As PdfField = TryCast(formWidget.FieldsWidget.List(i), PdfField)
				Dim fieldName As String = field.Name
				Dim isRequired As Boolean = field.Required
				If isRequired Then
					Console.WriteLine(fieldName & Convert.ToString(" is required."))
				End If
			Next
			Console.ReadKey()
		End Sub
	End Class
End Namespace

Form fields are often used in documents like surveys, registration forms, or feedback forms to collect data from users. Extracting form field values allows you to gather and consolidate the submitted data for further analysis or processing. In this article, we will demonstrate how to extract form field values from PDF documents in C# and VB.NET using Spire.PDF for .NET.

Install Spire.PDF for .NET

To begin with, you need to add the DLL files included in the Spire.PDF for.NET package as references in your .NET project. The DLLs files can be either downloaded from this link or installed via NuGet.

PM> Install-Package Spire.PDF

Extract Form Field Values from PDF in C# and VB.NET

In a PDF document, you may encounter various types of form fields, such as textboxes, checkboxes, radio buttons, list boxes, and combo boxes (drop-down lists). Before extracting form field values, it is crucial to identify the specific type of each form field. Once identified, you can utilize corresponding properties tailored for each form field type to accurately extract their values. The detailed steps are as follows:

  • Initialize an instance of the PdfDocument instance.
  • Load a PDF document using PdfDocument.LoadFromFile() method.
  • Initialize an instance of the StringBuilder class for storing the extract form field values.
  • Get the form from the document using PdfDocument.Form property.
  • Iterate through all form fields in the form.
  • Determine the types of the form fields, then get the names and values of the form fields using the corresponding properties and append them to the StringBuilder instance.
  • Write the content of the StringBuilder instance into a text file.
  • C#
  • VB.NET
using Spire.Pdf;
using Spire.Pdf.Fields;
using Spire.Pdf.Widget;
using System.IO;
using System.Text;

namespace ExtractFormFieldValues
{
    internal class Program
    {
        static void Main(string[] args)
        {            
            //Initialize an instance of the PdfDocument instance
            PdfDocument doc = new PdfDocument();
            //Load a PDF document
            doc.LoadFromFile(@"Forms.pdf");

            //Initialize an instance of the StringBuilder class
            StringBuilder sb = new StringBuilder();

            //Get the form from the document
            PdfFormWidget formWidget = doc.Form as PdfFormWidget;

            //Iterate through all fields in the form
            for (int i = 0; i < formWidget.FieldsWidget.List.Count; i++)
            {
                PdfField field = formWidget.FieldsWidget.List[i] as PdfField;

                //Get the name and value of textbox field
                if (field is PdfTextBoxFieldWidget)
                {
                    PdfTextBoxFieldWidget textBoxField = field as PdfTextBoxFieldWidget;                    
                    string name = textBoxField.Name;
                    string value = textBoxField.Text;
                    sb.Append("Textbox Name: " + name + "\r\n");
                    sb.Append("Textbox Value: " + value + "\r\n");
                }

                //Get the name, items and selected item of list box field
                if (field is PdfListBoxWidgetFieldWidget)
                {
                    PdfListBoxWidgetFieldWidget listBoxField = field as PdfListBoxWidgetFieldWidget;
                    string name = listBoxField.Name;
                    sb.Append("Listbox Name: " + name + "\r\n");
                    sb.Append("Listbox Items: \r\n");

                    PdfListWidgetItemCollection items = listBoxField.Values;

                    foreach (PdfListWidgetItem item in items)
                    {
                        sb.Append(item.Value + "\r\n");
                    }
                    string selectedValue = listBoxField.SelectedValue;
                    sb.Append("Listbox Selected Value: " + selectedValue + "\r\n");
                }

                //Get the name, items and selected item of combo box field
                if (field is PdfComboBoxWidgetFieldWidget)
                {
                    PdfComboBoxWidgetFieldWidget comBoxField = field as PdfComboBoxWidgetFieldWidget;
                    string name = comBoxField.Name;
                    sb.Append("Combobox Name: " + name + "\r\n");
                    sb.Append("Combobox Items: \r\n");
                    PdfListWidgetItemCollection items = comBoxField.Values;

                    foreach (PdfListWidgetItem item in items)
                    {
                        sb.Append(item.Value + "\r\n");
                    }
                    string selectedValue = comBoxField.SelectedValue;
                    sb.Append("Combobox Selected Value: " + selectedValue + "\r\n");

                }

                //Get the name and selected item of radio button field
                if (field is PdfRadioButtonListFieldWidget)
                {
                    PdfRadioButtonListFieldWidget radioBtnField = field as PdfRadioButtonListFieldWidget;
                    string name = radioBtnField.Name;
                    sb.Append("Radio Button Name: " + name + "\r\n");
                    string selectedValue = radioBtnField.SelectedValue;
                    sb.Append("Radio Button Selected Value: " + selectedValue + "\r\n");
                }

                //Get the name and status of checkbox field
                if (field is PdfCheckBoxWidgetFieldWidget)
                {
                    PdfCheckBoxWidgetFieldWidget checkBoxField = field as PdfCheckBoxWidgetFieldWidget;
                    string name = checkBoxField.Name;
                    sb.Append("Checkbox Name: " + name + "\r\n");
                    bool status = checkBoxField.Checked;
                    if (status)
                    {
                        sb.Append("Checkbox Status: Checked \r\n");
                    }
                    else
                    {
                        sb.Append("Checkbox Status: Unchecked \r\n");
                    }
                }

                sb.Append("\n");
            }

            //Write the content of the StringBuilder into a text file
            File.WriteAllText("GetAllValues.txt", sb.ToString());
            doc.Dispose();
        }
    }
}

C#/VB.NET: Extract Form Field Values from PDF

Apply for a Temporary License

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A text box can be formatted to display number, currency, date, time, zip code, phone number, social security number, etc. Adobe Acrobat provides various built-in JavaScripts, such as AFNumber_Keystroke(2, 0, 0, 0, "$", true) and AFNumber_Format(2, 0, 0, 0, "$", true), to format and validate the input of text field. The script with Format suffix is used to format the input, the script with Keystroke suffix is used to validate the input.

However, Spire.PDF has offered corresponding methods to perform formatting and validation on text field. Here is the list of frequently used formats and corresponding methods in Spire.PDF.

Description Example JavaScript Method
Date 01/31/2008 AFDate_FormatEx("mm/dd/yyyy");
AFDate_KeystrokeEx("mm/dd/yyyy");
GetDateFormatString("mm/dd/yyyy");
GetDateKeystrokeString("mm/dd/yyyy");
Date 1/31/2008 AFDate_FormatEx("m/d/yyyy");
AFDate_KeystrokeEx("m/d/yyyy");
GetDateFormatString("m/d/yyyy");
GetDateKeystrokeString("m/d/yyyy");
Zip code 12345 AFSpecial_Format(0);
AFSpecial_Keystroke(0);
GetSpecialFormatString(0);
GetSpecialKeystrokeString(0);
Zip+4 12345-1234 AFSpecial_Format(1);
AFSpecial_Keystroke(1);
GetSpecialFormatString(1);
GetSpecialKeystrokeString(1);
Phone number (123) 456-7890 AFSpecial_Format(2);
AFSpecial_Keystroke(2);
GetSpecialFormatString(2);
GetSpecialKeystrokeString(2);
Money (minus sign if negative) $12,345.00
-$12,345.00
AFNumber_Format(2, 0, 0, 0, "$", true);
AFNumber_Keystroke(2, 0, 0, 0, "$", true);
GetNumberFormatString(2, 0, 0, 0, "$", true);
GetNumberKeystrokeString(2, 0, 0, 0, "$", true);
Validate 1.5≤input value≤5.5 AFRange_Validate(true,1.5,true,5.5) GetRangeValidateString(true, 1.5, true, 5.5);

This tutorial demonstrates how to create a text box and display its contents in currency format in C# and VB.NET.

Code Snippets:

Step 1: Create an object of PdfDocument and add a page to it.

PdfDocument pdf = new PdfDocument();
PdfPageBase page = pdf.Pages.Add();

Step 2: Initialize an instance of PdfTextBoxField class and set its position, border width and border style.

PdfTextBoxField textbox = new PdfTextBoxField(page, "Number-TextBox");
textbox.Bounds = new RectangleF(10, 10, 100, 20);
textbox.BorderWidth = 0.75f;
textbox.BorderStyle = PdfBorderStyle.Solid;

Step 3: Set a JavaScript action to be performed when uses type a keystroke into a text field. This action can check the keystroke for validity and reject or modify it.

string js = PdfJavaScript.GetNumberKeystrokeString(2, 0, 0, 0, "$", true);
PdfJavaScriptAction jsAction = new PdfJavaScriptAction(js);
textbox.Actions.KeyPressed = jsAction;

Step 4: Set a JavaScript action to format the value of text field before showing it.

js = PdfJavaScript.GetNumberFormatString(2, 0, 0, 0, "$", true);
jsAction = new PdfJavaScriptAction(js);
textbox.Actions.Format = jsAction;

Step 5: Add the text box to PDF field and save the file.

pdf.Form.Fields.Add(textbox);
pdf.SaveToFile("FormatField.pdf",FileFormat.PDF);

Output:

How to Format Textbox Field using JavaScript in C#, VB.NET

Full Code:

[C#]
using Spire.Pdf;
using Spire.Pdf.Actions;
using Spire.Pdf.Fields;
using System.Drawing;

namespace FormatTextboxField
{
    class Program
    {
        static void Main(string []args)
        {
            PdfDocument pdf = new PdfDocument();
            PdfPageBase page = pdf.Pages.Add();
            PdfTextBoxField textbox = new PdfTextBoxField(page, "Number-TextBox");
            textbox.Bounds = new RectangleF(10, 10, 100, 20);
            textbox.BorderWidth = 0.75f;
            textbox.BorderStyle = PdfBorderStyle.Solid;

            string js = PdfJavaScript.GetNumberKeystrokeString(2, 0, 0, 0, "$", true);
            PdfJavaScriptAction jsAction = new PdfJavaScriptAction(js);
            textbox.Actions.KeyPressed = jsAction;

            js = PdfJavaScript.GetNumberFormatString(2, 0, 0, 0, "$", true);
            jsAction = new PdfJavaScriptAction(js);
            textbox.Actions.Format = jsAction;

            pdf.Form.Fields.Add(textbox);
            pdf.SaveToFile("FormatField.pdf", FileFormat.PDF);
        }
    }
}
[VB.NET]
Imports Spire.Pdf
Imports Spire.Pdf.Actions
Imports Spire.Pdf.Fields
Imports System.Drawing

Namespace FormatTextboxField
	Class Program
		Private Shared Sub Main(args As String())
			Dim pdf As New PdfDocument()
			Dim page As PdfPageBase = pdf.Pages.Add()
			Dim textbox As New PdfTextBoxField(page, "Number-TextBox")
			textbox.Bounds = New RectangleF(10, 10, 100, 20)
			textbox.BorderWidth = 0.75F
			textbox.BorderStyle = PdfBorderStyle.Solid

			Dim js As String = PdfJavaScript.GetNumberKeystrokeString(2, 0, 0, 0, "$", True)
			Dim jsAction As New PdfJavaScriptAction(js)
			textbox.Actions.KeyPressed = jsAction

			js = PdfJavaScript.GetNumberFormatString(2, 0, 0, 0, "$", True)
			jsAction = New PdfJavaScriptAction(js)
			textbox.Actions.Format = jsAction

			pdf.Form.Fields.Add(textbox)
			pdf.SaveToFile("FormatField.pdf", FileFormat.PDF)
		End Sub
	End Class
End Namespace

Tooltip is a message box that appears when users hover the pointer over the form field, providing users with instructions about the field, for instance, some extra information that users may find helpful in filling in the form field. This article presents how to add a tooltip to PDF form field using Spire.PDF in C# and VB.NET.

Code Snippet

Step 1: Initialize a new object of PdfDcoument class, add a page to it.

PdfDocument doc = new PdfDocument();
PdfPageBase page = doc.Pages.Add(PdfPageSize.A4, new PdfMargins(0));

Step 2: Add some text and a textbox on the PDF page.

PdfFont font = new PdfFont(PdfFontFamily.Helvetica, 12f,PdfFontStyle.Bold);
PdfBrush brush = PdfBrushes.Black;
float x = 50;
float y = 50;
float tempX = 0;
string text = "E-mail: ";
page.Canvas.DrawString(text, font, brush, x, y);
tempX = font.MeasureString(text).Width + x+15;
PdfTextBoxField textbox = new PdfTextBoxField(page, "TextBox");
textbox.Bounds = new RectangleF(tempX, y, 100, 15);
textbox.BorderWidth = 0.75f;
textbox.BorderStyle = PdfBorderStyle.Solid;
doc.Form.Fields.Add(textbox);

Step 3: The PdfDocument class provides a Fields collection which represents all form fields in the PDF document. You can get the specific field by its index or name, then set the value of ToolTip property to add a tooltip.

doc.Form.Fields["TextBox"].ToolTip = "Please insert a valid email address";

Step 4: Save and launch the file.

doc.SaveToFile("sample.pdf", FileFormat.PDF);
System.Diagnostics.Process.Start("sample.pdf");

Output:

Add Tooltip for PDF Form Field in C#, VB.NET

Full Code:

[C#]
using Spire.Pdf;
using Spire.Pdf.Fields;
using Spire.Pdf.Graphics;
using System.Drawing;


namespace AddTooltip
{
    class Program
    {
        static void Main(string []args)
        {
            PdfDocument doc = new PdfDocument();
            PdfPageBase page = doc.Pages.Add(PdfPageSize.A4, new PdfMargins(0));

            PdfFont font = new PdfFont(PdfFontFamily.Helvetica, 12f, PdfFontStyle.Bold);
            PdfBrush brush = PdfBrushes.Black;
            float x = 50;
            float y = 50;
            float tempX = 0;
            string text = "E-mail: ";
            page.Canvas.DrawString(text, font, brush, x, y);
            tempX = font.MeasureString(text).Width + x + 15;
            PdfTextBoxField textbox = new PdfTextBoxField(page, "TextBox");
            textbox.Bounds = new RectangleF(tempX, y, 100, 15);
            textbox.BorderWidth = 0.75f;
            textbox.BorderStyle = PdfBorderStyle.Solid;
            doc.Form.Fields.Add(textbox);

            doc.Form.Fields["TextBox"].ToolTip = "Please insert a valid email address";

            doc.SaveToFile("sample.pdf", FileFormat.PDF);
            System.Diagnostics.Process.Start("sample.pdf");
        }
    }
}
[VB.NET]
Imports Spire.Pdf
Imports Spire.Pdf.Fields
Imports Spire.Pdf.Graphics
Imports System.Drawing


Namespace AddTooltip
	Class Program
		Private Shared Sub Main(args As String())
			Dim doc As New PdfDocument()
			Dim page As PdfPageBase = doc.Pages.Add(PdfPageSize.A4, New PdfMargins(0))

			Dim font As New PdfFont(PdfFontFamily.Helvetica, 12F, PdfFontStyle.Bold)
			Dim brush As PdfBrush = PdfBrushes.Black
			Dim x As Single = 50
			Dim y As Single = 50
			Dim tempX As Single = 0
			Dim text As String = "E-mail: "
			page.Canvas.DrawString(text, font, brush, x, y)
			tempX = font.MeasureString(text).Width + x + 15
			Dim textbox As New PdfTextBoxField(page, "TextBox")
			textbox.Bounds = New RectangleF(tempX, y, 100, 15)
			textbox.BorderWidth = 0.75F
			textbox.BorderStyle = PdfBorderStyle.Solid
			doc.Form.Fields.Add(textbox)

			doc.Form.Fields("TextBox").ToolTip = "Please insert a valid email address"

			doc.SaveToFile("sample.pdf", FileFormat.PDF)
			System.Diagnostics.Process.Start("sample.pdf")
		End Sub
	End Class
End Namespace
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