I have a XML file(web.config) and I need to edit the value attribute of each tag, depend of the key name...

this is an example of the XML file:

```
<appSettings>
  <add key="A1" value="Hi" />
  <add key="B1" value="Hello" />
</appSettings>

```

I mean, How can I change the value "hi" & "hello" using the key attribute(A1 & B1) ??

Thanks alot