Gets or sets the character to use for indenting when XmlTextWriter.Formatting is set to Formatting.Indented.
A char specifying the character to use for indenting. The default is space (character code 0x20).
This property can be set to any character. To ensure valid XML, set this property to a valid white space character: 0x9, 0x10, 0x13, or 0x20.