How can I use the memberwiseclone method in c#?

Question

The method MemberwiseClone is applied to many collections like arraylist etc,how can I implement this method?also give an example?

Vulpes · Answer

Here's a simple example of using the MemberwiseClone method in C#. Notice that the integer field is deep copied as it's a value type. Even though it's a reference type, the string field is also deep copied as it's immutable - when a change is made a new string object is created rather than the old one being changed. However, the reference type (SomeClass) is shallow copied - when a change is made to SomeInt it's still part of the same object and so the change is reflected in the clone: using System; class SomeClass { public int SomeInt {get; set;} } class MyClass { public int MyInt {get; set;} // value type public string MyString {get; set;} // immutable reference type public SomeClass SomeObject {get; set;} // mutable reference type public MyClass(int myInt, string myString, SomeClass someObject) { MyInt = myInt; MyString = myString; SomeObject = someObject; } public MyClass Clone() { return (MyClass)MemberwiseClone(); } } class Test { static void Main() { SomeClass sc = new SomeClass(); sc.SomeInt = 42; MyClass mc = new MyClass(1, "Hello", sc); // now clone 'mc' MyClass mc2 = mc.Clone(); // change 'mc' mc.MyInt = 2; mc.MyString = "Goodbye"; mc.SomeObject.SomeInt = 43; // check 'mc2' to see what has changed Console.WriteLine(mc2.MyInt); // still 1 Console.WriteLine(mc2.MyString); // still Hello Console.WriteLine(mc2.SomeObject.SomeInt); // now 43 Console.ReadKey(); } }

Jignesh Trivedi · Answer

hi Richa, The MemberwiseClone method creates a shallow copy by creating a new object, and then copying the nonstatic fields of the current object to the new object. If a field is a value type, a bit-by-bit copy of the field is performed. If a field is a reference type, the reference is copied but the referred object is not; therefore, the original object and its clone refer to the same object. Please refer, http://msdn.microsoft.com/en-us/library/system.object.memberwiseclone%28v=vs.80%29.aspx http://dotnetgurukul.com/2011/02/24/cloning-in-c-shallow-copy-using-memberwiseclone-method/ hope this will help u.

Satyapriya Nayak · Answer

Hi Richa, Please refer the below links http://msdn.microsoft.com/en-us/library/system.object.memberwiseclone.aspx http://buttle.shangorilla.com/1.1/handlers/monodoc.ashx?link=M%3ASystem.Object.MemberwiseClone Thanks

How can I use the memberwiseclone method in c#?

Answers (3)