TagGetID Method (GdViewer)

In This Topic

Returns a unique tag ID (a proper tag name defined by the specification) of the required tag, that is embedded within the document displayed in the GdViewer control.

Syntax

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

'Declaration
 
Public Function TagGetID( _
   ByVal TagNo As Integer _
) As Tags

public Tags TagGetID( 
   int TagNo
)

public function TagGetID( 
    TagNo: Integer
): Tags;

public function TagGetID( 
   TagNo : int
) : Tags;

public: Tags TagGetID( 
   int TagNo
)

public:
Tags TagGetID( 
   int TagNo
)

Parameters

TagNo: The sequence index of the required tag within the displayed document. It must be a value from 1 to TagCount.

Return Value

A member of the Tags enumeration. The GetStat method can be subsequently used to determine if this method has been successful.

Remarks

It is recommend to use the GetStat method to identify the specific reason for the method's failure, if any.

This method handles EXIF tags, IPTC tags, Extra tags (like Adobe Image Information tags etc.), Thumbnail related tags, GPS tags and XML packet metadata.

Example

How to find out the tag's ID (a unique predefined tag name).

VB.NET
C#

'We assume that the GdViewer1 control has been properly integrated
'and your document has been properly displayed as well.
Dim count As Integer = GdViewer1.TagCount()
If GdViewer1.GetStat() = GdPictureStatus.OK Then
    Dim message As String = "Tags count: " + count + vbCrLf
    Dim tagID As Tags = Tags.TagUnknown
    Dim tagName As String = "", tagValue As String = ""
    For i As Integer = 1 To count
        tagID = GdViewer1.TagGetID(i)
        If GdViewer1.GetStat() = GdPictureStatus.OK Then tagName = GdViewer1.TagGetName(i)
        If GdViewer1.GetStat() = GdPictureStatus.OK Then tagValue = GdViewer1.TagGetValueString(i)
            
        If GdViewer1.GetStat() = GdPictureStatus.OK Then
            message = message + vbCrLf + tagName + " (" + tagID + "): " + tagValue
        Else
            message = message + vbCrLf + "Tag nr." + i + "  Status: " + GdViewer1.GetStat().ToString()
        End If
    Next
    MessageBox.Show(message, "GdViewer.TagGetID")
Else
    MessageBox.Show("The number of tags can't be found. Status: " + GdViewer1.GetStat().ToString(), "GdViewer.TagGetID")
End If

//We assume that the GdViewer1 control has been properly integrated
//and your document has been properly displayed as well.
int count = GdViewer1.TagCount();
if (GdViewer1.GetStat() == GdPictureStatus.OK)
{
    string message = "Tags count: " + count + "\n";
    Tags tagID = Tags.TagUnknown;
    string tagName = "", tagValue = "";
    for (int i = 1; i <= count; i++)
    {
        tagID = GdViewer1.TagGetID(i);
        if (GdViewer1.GetStat() == GdPictureStatus.OK)
            tagName = GdViewer1.TagGetName(i);
        if (GdViewer1.GetStat() == GdPictureStatus.OK)
            tagValue = GdViewer1.TagGetValueString(i);
        if (GdViewer1.GetStat() == GdPictureStatus.OK)
            message = message + "\n" + tagName + " (" + tagID + "): " + tagValue;
        else
            message = message + "\nTag nr." + i + "  Status: " + GdViewer1.GetStat().ToString();
    }
    MessageBox.Show(message, "GdViewer.TagGetID");
}
else
    MessageBox.Show("The number of tags can't be found. Status: " + GdViewer1.GetStat().ToString(), "GdViewer.TagGetID");

Reference

GdViewer Class
GdViewer Members
TagCount Method
TagGetName Method
TagGetValueString Method
IPTCCount Method