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How do I check if a property exists on a dynamic anonymous type in c#?
....
var settings = new {
                   Filename="temp.txt",
                   Size=10
}
...

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

public static bool IsSettingsExist(dynamic settings, string name)
  {
    return settings.GetType().GetProperty(name) != null;
  }

  var settings = new {Filename = @"c:tempq.txt"};
  Console.WriteLine(IsSettingsExist(settings, "Filename"));
  Console.WriteLine(IsSettingsExist(settings, "Size"));

True
 False

dynamic settings = new ExpandoObject();
settings.Filename = "asdf.txt";
settings.Size = 10;
...

function void Settings(dynamic settings)
{
    if ( ((IDictionary<string, object>)settings).ContainsKey("Filename") )
        .... do something ....
}