XML attribute '{0}' is not defined
XML attribute '{0}' is not defined. Expected xml:space or xml:lang.
This error occurs when you use an attribute scoped to the xml namespace which is not defined. The only valid attributes in the xml namespace are xml:space and xml:lang.
This error is raised when the file is a valid XML document, but is not a well-formed XAML document.
Error ID: XAML0423
To correct this error
- Change the attribute to one of the valid values for an xml namespace attribute, xml:space and xml:lang.
To correct this error
- Check the spelling of the xml namespace attribute.
Example
The following code example shows valid assignments to the xml:space and xml:lang attributes.
<Button xml:space='preserve'> OK </Button>
<Button xml:lang='rfc3066lang'>OK</Button>
<!-- Uncomment the following line to raise error XAML0423. -->
<!-- <Button xml:unknown='default'> OK </Button> -->