public PdfFormData this[string name] { get; set; }

Public Property Item(name As String) As PdfFormData

// Load a document with an interactive form.
using (PdfDocumentProcessor documentProcessor = new PdfDocumentProcessor()) {
    documentProcessor.LoadDocument(filePath + fileName + ".pdf");

    // Obtain interactive form data from a document.
    PdfFormData formData = documentProcessor.GetFormData();

    // Specify the value for FirstName and LastName text boxes.
    formData["FirstName"].Value = "Janet";
    formData["LastName"].Value = "Leverling";

    // Specify the value for the Gender radio group.
    formData["Gender"].Value = "Female";

    // Specify the check box checked appearance name.
    formData["Check"].Value = "Yes";

    // Specify values for the Category list box.
    formData["Category"].Value = new string[] { "Entertainment", "Meals", "Morale" };

    // Obtain data from the Address form field and specify values for Address child form fields.
    PdfFormData address = formData["Address"];

    // Specify the value for the Country combo box. 
    address["Country"].Value = "United States";

    // Specify the value for City and Address text boxes. 
    address["City"].Value = "California";
    address["Address"].Value = "20 Maple Avenue";

    // Apply data to the interactive form. 
    documentProcessor.ApplyFormData(formData);

    // Save the modified document.
    documentProcessor.SaveDocument(filePath + fileName + "_new.pdf");
}

' Load a document with an interactive form.
Using documentProcessor As New PdfDocumentProcessor()
    documentProcessor.LoadDocument(filePath & fileName & ".pdf")

    ' Obtain interactive form data from a document.
    Dim formData As PdfFormData = documentProcessor.GetFormData()

    ' Specify the value for FirstName and LastName text boxes.
    formData("FirstName").Value = "Janet"
    formData("LastName").Value = "Leverling"

    ' Specify the value for the Gender radio group.
    formData("Gender").Value = "Female"

    ' Specify the check box checked appearance name.
    formData("Check").Value = "Yes"

    ' Specify values for the Category list box.
    formData("Category").Value = New String() { "Entertainment", "Meals", "Morale" }

    ' Obtain data from the Address form field and specify values for Address child form fields.
    Dim address As PdfFormData = formData("Address")

    ' Specify the value for the Country combo box. 
    address("Country").Value = "United States"

    ' Specify the value for City and Address text boxes. 
    address("City").Value = "California"
    address("Address").Value = "20 Maple Avenue"

    ' Apply data to the interactive form. 
    documentProcessor.ApplyFormData(formData)

    ' Save the modified document.
    documentProcessor.SaveDocument(filePath & fileName & "_new.pdf")

End Using