Artigo
11/18/2011

XmlNamespaceManager.HasNamespace Method

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Gets a value indicating whether the supplied prefix has a namespace defined for the current pushed scope.

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

Syntax

'Declaration
Public Overridable Function HasNamespace ( _
    prefix As String _
) As Boolean

public virtual bool HasNamespace(
    string prefix
)

Parameters

prefix
Type: System.String
The prefix of the namespace you want to find.

Return Value

Type: System.Boolean
true if there is a namespace defined; otherwise, false.

Remarks

To determine whether there is a default empty namespace defined, set prefix to String.Empty. If the method returns true, this indicates that there is a default namespace defined in the current scope. Returning false indicates that no default namespace is defined.

Note:
xmlns:x= "" is illegal according to W3C Namespaces in XML recommendation.

Examples

Dim output As New StringBuilder()
' Create the XmlNamespaceManager.
Dim nt As New NameTable()
Dim nsmgr As 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")

Dim prefix As String = 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()

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();

Version Information

Silverlight

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

Platforms

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

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