Sets the value of an attribute, adds an attribute, or removes an attribute.
Assembly: System.Xml.Linq (in System.Xml.Linq.dll)
This method is designed to make it easy to maintain a list of name/value pairs as a set of attributes. When maintaining the list, you need to add pairs, modify pairs, or delete pairs. If you call this method passing a name that does not exist as an attribute, this method creates an attribute for you. If you call this method passing the name of an existing attribute, this method modifies the value of the attribute to the value that you specify. If you pass a null reference (Nothing in Visual Basic) for value, this method removes the attribute.
The value is assigned to the attribute with the specified name. If no attribute with the specified name exists, a new attribute is added. If the value is a null reference (Nothing in Visual Basic), the attribute with the specified name, if any, is deleted.
For more information, see Maintaining Name/Value Pairs.
The following example creates an element with an attribute. It then uses this method to replace the content of the attribute.
This example produces the following output:
<Root Att1="1" Att2="2" Att3="3" /> <Root Att1="1" Att2="22" Att3="3" /> <Root Att1="1" Att2="22" />