Find a key in NameValueCollection

Question

I am trying to find a key in the namevaluecollection. If the key is found then next piece of code should execute else not.

My Web.config has below configuration:

  <Dropdownvalue>
    <add key="5" value="Yes" />
    <add key="8" value="No" />
    <add key="9" value="Maybe" />
  </Dropdownvalue>

My code is:

public string getMyId(int MyId)
{
    NameValueCollection colMaster = (NameValueCollection)ConfigurationManager.GetSection("Dropdownvalue");

    if (colMaster[MyId] != null)
    {
        //execute code
    }
}

When MyId = 9, I get below error for the obvious reason that it is trying to fetch 9th record instead of comparing MyId with Key 9.

System.ArgumentOutOfRangeException: 'Index was out of range. 

I know that below code would work perfectly fine:

colMaster["9"]

However, my value changes dynamically so this won't work in my scenario.

Is there a way in namevaluecollection or outside it to access keys from web.config ?

Answer 1

Your problem is that MyID is not a string. Look at the following code:

    static void Main(string[] args)
    {
        var nvc = new NameValueCollection {{"5", "first value"}, {"6", "second value"}, {"9", "third value"}};

        Console.WriteLine(nvc["5"]); // first value
        Console.WriteLine(nvc[1]);   // second value
        Console.WriteLine(nvc[3]);   // index was out of range
    }

nvc[0] would print first value. Convert MyID to string to make it work.