Question

I find that Add method and Set method are same function but I don’t know what different in this 2 method? Can explain it?

Answer 1

Methods are mapped to Dictionary Add and indexer methods. The Add method will throw an exception if the key already exists. Set method will override existing value.

ASPxHiddenField hiddenField = new ASPxHiddenField();
hiddenField.Add("key1", "value1");
hiddenField.Set("key1", "value2");  // this will properly set key1 value
hiddenField.Add("key1", "value3");  // this will throw exception