Specifies that the property this attribute is bound to is read-only and cannot be modified in the server explorer. This static field is read-only.
When you mark a property with the System.ComponentModel.ReadOnlyAttribute set to true, the value of this attribute is set to the constant member ReadOnlyAttribute.Yes. Therefore, when you want to check whether the attribute is set to this value in your code, you must specify the attribute as ReadOnlyAttribute.Yes.