XmlNamespaceManager.LookupPrefix Method

Finds the prefix declared for the given namespace URI.

Namespace:  System.Xml
Assembly:  System.Xml (in System.Xml.dll)

public virtual string LookupPrefix(
	string uri


Type: System.String
The namespace to resolve for the prefix.

Return Value

Type: System.String
The matching prefix. If there is no mapped prefix, the method returns String.Empty. If a null value is supplied, then null is returned.



This method finds the mapped prefix by walking the stack (that is, it looks globally). The supplied string must be atomized for the lookup to succeed. In other words, the supplied string object must exist in the XmlNamespaceManager's NameTable.

The returned string is also atomized. For more information on atomized strings, see XmlNameTable.

StringBuilder output = new StringBuilder();
// Create the XmlNamespaceManager.
NameTable nt = new NameTable();
XmlNamespaceManager nsmgr = new XmlNamespaceManager(nt);

// Add prefix/namespace pairs to the XmlNamespaceManager.
nsmgr.AddNamespace("", "www.wideworldimporters.com"); //Adds a default namespace.
nsmgr.AddNamespace("europe", "www.wideworldimporters.com/europe");

String prefix = nsmgr.LookupPrefix("www.wideworldimporters.com/europe");
output.AppendLine(" Before removing prefix: " + prefix);
nsmgr.RemoveNamespace(prefix, "www.wideworldimporters.com/europe");
output.Append(" Before removing prefix: " + nsmgr.LookupPrefix("www.wideworldimporters.com/europe"));

OutputTextBlock.Text = output.ToString();


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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