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HtmlElement.GetAttribute(String) Method

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll
Source:
HtmlElement.cs
Source:
HtmlElement.cs
Source:
HtmlElement.cs

Retrieves the value of the named attribute on the element.

public:
 System::String ^ GetAttribute(System::String ^ attributeName);
public string GetAttribute (string attributeName);
member this.GetAttribute : string -> string
Public Function GetAttribute (attributeName As String) As String

Parameters

attributeName
String

The name of the attribute. This argument is case-insensitive.

Returns

String

The value of this attribute on the element, as a String value. If the specified attribute does not exist on this element, returns an empty string.

Examples

The following code example retrieves all of the META tags within an HTML document, using GetAttribute to find the META tag with the name Description. The example requires that your application has a WebBrowser control named WebBrowser1.

private void DisplayMetaDescription()
{
    if (webBrowser1.Document != null)
    {
        HtmlElementCollection elems = webBrowser1.Document.GetElementsByTagName("META");
        foreach (HtmlElement elem in elems)
        {
            String nameStr = elem.GetAttribute("name");
            if (nameStr != null && nameStr.Length != 0)
            {
                String contentStr = elem.GetAttribute("content");
                MessageBox.Show("Document: " + webBrowser1.Url.ToString() + "\nDescription: " + contentStr);
            }
        }
    }
}

Private Sub DisplayMetaDescription()
    If (WebBrowser1.Document IsNot Nothing) Then
        Dim Elems As HtmlElementCollection 
        Dim WebOC as WebBrowser = WebBrowser1

    Elems = WebOC.Document.GetElementsByTagName("META")

        For Each elem As HtmlElement In Elems
            Dim NameStr As String = elem.GetAttribute("name")

            If ((NameStr IsNot Nothing) And (NameStr.Length <> 0)) Then
                If NameStr.ToLower().Equals("description") Then
                    Dim ContentStr As String = elem.GetAttribute("content")
                    MessageBox.Show("Document: " & WebOC.Url.ToString() & vbCrLf & "Description: " & ContentStr)
                End If
            End If
        Next
    End If
End Sub

Remarks

An attribute in HTML is any valid name/value pair for that element. HtmlElement exposes only those attributes that are common to all elements, leaving out those that only apply to certain types of elements; SRC is a predefined attribute for the IMG tag, for example, but not for the DIV tag. Use GetAttribute and SetAttribute to manipulate attributes not exposed on the managed Document Object Model (DOM).

GetAttribute and SetAttribute are case-insensitive.

Applies to

See also