How do I check if a property exists on a dynamic anonymous type in c#?

c# c#-4.0 dynamic reflection .net-4.0
David MZ picture David MZ · Mar 31, 2012 · Viewed 112.5k times · Source

I have an anonymous type object that I receive as a dynamic from a method I would like to check in a property exists on that object.

....
var settings = new {
                   Filename="temp.txt",
                   Size=10
}
...

function void Settings(dynamic settings) {
var exists = IsSettingExist(settings,"Filename")
}

How would I implement IsSettingExist ?

Answer

Serj-Tm picture Serj-Tm · Mar 31, 2012 
  public static bool IsPropertyExist(dynamic settings, string name)
  {
    if (settings is ExpandoObject)
      return ((IDictionary<string, object>)settings).ContainsKey(name);

    return settings.GetType().GetProperty(name) != null;
  }

  var settings = new {Filename = @"c:\temp\q.txt"};
  Console.WriteLine(IsPropertyExist(settings, "Filename"));
  Console.WriteLine(IsPropertyExist(settings, "Size"));

Output:

 True
 False

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