eSign document with Form Field signature Leave feedback

A form field is an interactive element located on a document page that allows user data input through various control types like free input text boxes, multi-line text boxes, checkboxes, drop-down lists, etc. Different document types support a specific list of form field types. These elements are used to collect information from users on template form. Each Form Field element has a unique name, settings and value field. Form Fields should have unique names within the form. The picture below demonstrates a possible document page with form fields.

With GroupDocs.Signature you can create new form fields or update the existing ones within the documents. The FormFieldSignOptions class specifies different options for Form Field signature. The FormFieldSignOptions class contains one FormFieldSignature object that specifies the properties of the desired signature.

Below are listed different Form Field signature classes that could be set to FormFieldSignOptions:

• TextFormFieldSignature - represents a text input form field on a document page.
• CheckboxFormFieldSignature - represents a checkbox field on a document page.
• ComboboxFormFieldSignature - represents a combo box field signature input with a list of possible options.
• RadioButtonFormFieldSignature - represents a radio button signature on a document page.
• DigitalFormFieldSignature - represents a digital signature input form on a document page.

Here are the steps to add Form Field signatures into a document with GroupDocs.Signature:

• Create a new instance of the Signature class and pass the source document path as a constructor parameter;
• Instantiate the FormFieldSignOptions object according to your requirements;
• Instantiate one of the objects - TextFormFieldSignature, CheckboxFormFieldSignature, ComboboxFormFieldSignature, RadioButtonFormFieldSignature or DigitalFormFieldSignature;
• Assign the FormFieldSignOptions property with the object created in a previous step;
• Call the Sign method of the Signature class instance and pass the FormFieldSignOptions object to it.

Note

Currently GroupDocs.Signature supports the creation of Form Field signatures for PDF documents only.

This example shows how to sign a PDF document with a Form Field electronic signature.

            // The path to the documents directory.
            string filePath = "sample.pdf";
            string fileName = Path.GetFileName(filePath);

            string outputFilePath = Path.Combine("C:\output", fileName);

            using (Signature signature = new Signature(filePath))
            {
                // Instantiate text form field signature
                FormFieldSignature textSignature = new TextFormFieldSignature("FieldText", "Value1");

                // Instantiate options based on text form field signature
                FormFieldSignOptions options = new FormFieldSignOptions(textSignature)
                {
                    HorizontalAlignment = HorizontalAlignment.Left,
                    VerticalAlignment = VerticalAlignment.Top,
                    Margin = new Padding(10, 20, 0, 0),
                    Height = 10,
                    Width = 100
                };
                // Sign document and save to the file
                signature.Sign(outputFilePath, options);
            }

GroupDocs.Signature for .NET also provides a mechanism to update the existing form field signatures within the documents.

To update an existing form field signature within the document with GroupDocs.Signature:

• Create a new instance of the Signature class and pass the source document path as a constructor parameter.
• Instantiate the TextSignOptions object with all required additional options.
• Set the TextSignOptions.SignatureImplementation property with the TextSignatureImplementation.FormField value.
• Set the FormTextFieldTitle and FormTextFieldType properties with the proper values of form fields to be updated.
• Call the Sign method of the Signature class instance and pass the initialized TextSignOptions instance to it.
• Analyze the SignResult object to check the newly created signatures if needed.

This example shows how to sign a PDF document with the existing Form Field electronic signature and update its value.

// The path to the documents directory.
string filePath = "sample.pdf";
string fileName = Path.GetFileName(filePath);

string outputFilePath = Path.Combine("C:\output", fileName);

using (Signature signature = new Signature(filePath))
{
    TextSignOptions ffOptions1 = new TextSignOptions("Document is approved")
    {
        // set alternative signature implementation on document page
        SignatureImplementation = TextSignatureImplementation.FormField,
        FormTextFieldType = FormTextFieldType.PlainText
    };
    TextSignOptions ffOptions2 = new TextSignOptions("John Smith")
    {
        // set alternative signature implementation on document page
        SignatureImplementation = TextSignatureImplementation.FormField,
        FormTextFieldType = FormTextFieldType.RichText,
        FormTextFieldTitle = "UserSignatureFullName"
    };
    List<SignOptions> listOptions = new List<SignOptions>();
    listOptions.Add(ffOptions1);
    listOptions.Add(ffOptions2);
    // sign document to file
    SignResult signResult = signature.Sign(outputFilePath, listOptions);
}

This guide explains how to use GroupDocs.Signature to add form field signatures to documents. It covers loading a document, configuring form field properties such as name, type, and value, and saving the signed document. Advanced options, like customizing field appearance and placement, are also included. For more details, refer to related guides on document signing techniques.

To learn more about document eSign features, please refer to the advanced usage section.

You may easily run the code above and see the feature in action in our GitHub examples:

• GroupDocs.Signature for .NET examples, plugins, and showcase
• GroupDocs.Signature for Java examples, plugins, and showcase
• Document Signature for .NET MVC UI Example
• Document Signature for .NET App WebForms UI Example
• Document Signature for Java App Dropwizard UI Example
• Document Signature for Java Spring UI Example

Along with the full-featured .NET library, we provide simple but powerful free online apps.

To sign PDF documents for free, you can use the Digital Signature - PDF online application.

To sign Word, Excel, PowerPoint, and other documents you can use the other online apps from the GroupDocs.Signature App Product Family.