c# - Why XmlSerializer adding garbage value to end tag of the root element? -

i trying write value xml values using xmlserializer , below code. code called on selection change of dropdown list. first time works fine second selection change event inserts garbage value xml shown below.

protected void updatedefaultreasonconfig(object sender, eventargs e)     {         string configfile = configurationsettings.appsettings["defaultoutagereasonconfig"];          defaultoutagereason defaultoutagereason = new defaultoutagereason();         defaultoutagereason.outagereason = this._defaultoutagereason.text;         xmlserializer writer = new xmlserializer(typeof(defaultoutagereason));         using (filestream write = file.openwrite(configfile))         {             writer.serialize(write, defaultoutagereason);         }     } 

and resulting xml is:

<?xml version="1.0"?> <defaultoutagereason xmlns:xsi="http://www.w3.org/2001/xmlschema-instance" xmlns:xsd="http://www.w3.org/2001/xmlschema">   <outagereason>storm damage</outagereason> </defaultoutagereason>eason> 

so please me why adding value end tag of root.

you need file.create instead of file.openwrite because overwrites old one, , if new file shorter see garbage.