How to check whether a value exists in xml file or not in vb.net
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I am trying to check weather a string is exists in the xml file or not. if not exists i have to add that string to the xml file.

My xml file looks like this
   

      <Employee>
          <Emp>
            <Name id="1">   A     </Name>
            <Name id="2">   C     </Name>
            <Name id="3">   D     </Name>
           </Emp>
          </Employee>

And i want achieve

    dim str as string = "b" 
    if str exists in "xmlfile"
    'do somethng
    else
    'add string to file
    end if


I am not aware of LINQ at all but i understood that we can do it with LINQ, i tried the following bit

    Dim employee = XElement.Load(someStream)
    Dim emp = employee.Element("Emp")
    If emp IsNot Nothing Then
    	else
            'add string to xml file
    End If

when i tried this it saying `XElement` is not declared.

Can any one suggest if it can be achievable in VB.NET without LINQ or if i have to use can some suugest some steps please as i am new to LINQ

I am using .net 2.0 (VB.NET)