RemoveFormField Method (GdPicturePDF)

In This Topic

Removes a required form field, that is specified by its unique form field's identifier and it is related to the currently loaded PDF document.

Syntax

Visual Basic
C#
Delphi
JScript
Managed Extensions for C++
C++/CLI

'Declaration
 
Public Function RemoveFormField( _
   ByVal FieldId As Integer _
) As GdPictureStatus

public GdPictureStatus RemoveFormField( 
   int FieldId
)

public function RemoveFormField( 
    FieldId: Integer
): GdPictureStatus;

public function RemoveFormField( 
   FieldId : int
) : GdPictureStatus;

public: GdPictureStatus RemoveFormField( 
   int FieldId
)

public:
GdPictureStatus RemoveFormField( 
   int FieldId
)

Parameters

FieldId: A unique form field identifier specifying a required form field object. You can obtain this identifier using methods like GetFormFieldId, GetFormFieldChildID or methods intended to add form fields.

Return Value

A member of the GdPictureStatus enumeration. If the method has been successfully followed, then the return value is GdPictureStatus.OK.

We strongly recommend always checking this status first.

Remarks

This method is only allowed for use with non-encrypted documents.

Example

How to remove all push buttons from the current document.

VB.NET
C#

Dim caption As String = "Example: RemoveFormField"
Dim gdpicturePDF As GdPicturePDF = New GdPicturePDF()
If gdpicturePDF.LoadFromFile("forms.pdf", False) = GdPictureStatus.OK Then
    Dim count As Integer = gdpicturePDF.GetFormFieldsCount()
    If gdpicturePDF.GetStat() = GdPictureStatus.OK Then
        Dim formID As Integer = 0, removedCount As Integer = 0
        Dim type As PdfFormFieldType = PdfFormFieldType.PdfFormFieldTypeUnknown
        For i As Integer = 0 To count - 1
            formID = gdpicturePDF.GetFormFieldId(i)
            If gdpicturePDF.GetStat() = GdPictureStatus.OK Then
                type = gdpicturePDF.GetFormFieldType(formID)
                If gdpicturePDF.GetStat() = GdPictureStatus.OK Then
                    If type = PdfFormFieldType.PdfFormFieldTypePushButton Then
                        If gdpicturePDF.RemoveFormField(formID) = GdPictureStatus.OK Then
                            removedCount += 1
                            count -= 1
                        Else
                            MessageBox.Show("The RemoveFormField() method has failed with the status: " + gdpicturePDF.GetStat().ToString(), caption)
                            Exit For
                        End If
                    End If
                Else
                    MessageBox.Show("The GetFormFieldType() method has failed with the status: " + gdpicturePDF.GetStat().ToString(), caption)
                    Exit For
                End If
            Else
                MessageBox.Show("The GetFormFieldId() method has failed with the status: " + gdpicturePDF.GetStat().ToString(), caption)
                Exit For
            End If
        Next
        If gdpicturePDF.GetStat() = GdPictureStatus.OK Then
            If gdpicturePDF.SaveToFile("forms_removed.pdf") = GdPictureStatus.OK Then
                MessageBox.Show("Number of removed push buttons: " + removedCount.ToString() + vbCrLf + "The example has been followed successfully and the file has been saved.", caption)
            Else
                MessageBox.Show("The file can't be saved. Status: " + gdpicturePDF.GetStat().ToString(), caption)
            End If
        End If
    Else
        MessageBox.Show("The GetFormFieldsCount() method has failed with the status: " + gdpicturePDF.GetStat().ToString(), caption)
    End If
Else
    MessageBox.Show("The file can't be loaded. Status: " + gdpicturePDF.GetStat().ToString(), caption)
End If
gdpicturePDF.Dispose()

string caption = "Example: RemoveFormField";
GdPicturePDF gdpicturePDF = new GdPicturePDF();
if (gdpicturePDF.LoadFromFile("forms.pdf", false) == GdPictureStatus.OK)
{
    int count = gdpicturePDF.GetFormFieldsCount();
    if (gdpicturePDF.GetStat() == GdPictureStatus.OK)
    {
        int formID = 0, removedCount = 0;
        PdfFormFieldType type = PdfFormFieldType.PdfFormFieldTypeUnknown;
        for (int i = 0; i < count; i++)
        {
            formID = gdpicturePDF.GetFormFieldId(i);
            if (gdpicturePDF.GetStat() == GdPictureStatus.OK)
            {
                type = gdpicturePDF.GetFormFieldType(formID);
                if (gdpicturePDF.GetStat() == GdPictureStatus.OK)
                {
                    if (type == PdfFormFieldType.PdfFormFieldTypePushButton)
                        if (gdpicturePDF.RemoveFormField(formID) == GdPictureStatus.OK)
                        {
                            removedCount++;
                            count--;
                        }
                        else
                        {
                            MessageBox.Show("The RemoveFormField() method has failed with the status: " + gdpicturePDF.GetStat().ToString(), caption);
                            break;
                        }
                }
                else
                {
                    MessageBox.Show("The GetFormFieldType() method has failed with the status: " + gdpicturePDF.GetStat().ToString(), caption);
                    break;
                }
            }
            else
            {
                MessageBox.Show("The GetFormFieldId() method has failed with the status: " + gdpicturePDF.GetStat().ToString(), caption);
                break;
            }
        }
        if (gdpicturePDF.GetStat() == GdPictureStatus.OK)
        {
            if (gdpicturePDF.SaveToFile("forms_removed.pdf") == GdPictureStatus.OK)
                MessageBox.Show("Number of removed push buttons: " + removedCount.ToString() + "\nThe example has been followed successfully and the file has been saved.", caption);
            else
                MessageBox.Show("The file can't be saved. Status: " + gdpicturePDF.GetStat().ToString(), caption);
        }
    }
    else
        MessageBox.Show("The GetFormFieldsCount() method has failed with the status: " + gdpicturePDF.GetStat().ToString(), caption);
}
else
    MessageBox.Show("The file can't be loaded. Status: " + gdpicturePDF.GetStat().ToString(), caption);
gdpicturePDF.Dispose();

Reference

GdPicturePDF Class
GdPicturePDF Members
GetFormFieldsCount Method
GetFormFieldId Method
GetFormFieldChildID Method
GetFormFieldType Method
RemoveFormFields Method
FlattenFormFields Method