What is the differnce between ref and out keyword in c#?

Question

Ajay Gohil · Answer

The main difference is that you have to initialize (or assign a value to) variable in the main method before passing it by ref keyword. However, you don’t have to initialize it in the main method if you are passing it by out parameter static void Main( string [] args) { int data= 5; string returnText1 = PrintNumber1( ref data); string returnText2 = PrintNumber2( out data); Console.WriteLine( "Passed by ref: " + returnText1.ToString()); Console.WriteLine( "Passed by out: " + returnText2.ToString()); Console.ReadLine(); } public static string PrintNumber1( ref int data) { // No initialization here return data.ToString(); } public static string PrintNumber2( out int data) { data= 6; // It must be initialized here return data.ToString(); } output: Passed by ref:5 Passed by out:6

Rajanikant Hawaldar · Answer

Hi Anil Kumar, Go through through these articles which contains explaination with example let me know if you not understand. https://www.geeksforgeeks.org/difference-between-ref-and-out-keywords-in-c-sharp/ https://www.c-sharpcorner.com/UploadFile/ff2f08/ref-vs-out-keywords-in-C-Sharp/ https://www.c-sharpcorner.com/blogs/difference-between-ref-and-out-parameters https://csharp-station.com/ref-parameters-vs-out-parameters https://www.dotnettricks.com/learn/csharp/difference-between-ref-and-out-parameters https://stackoverflow.com/questions/135234/difference-between-ref-and-out-parameters-in-net Thanks

Chittaranjan Swain · Answer

Hi Anil, Refer Below links, Out keywords in C# The out is a keyword in C# which is used for the passing the arguments to methods as a reference type. It is generally used when a method returns multiple values. ... The ref is a keyword in C# which is used for the passing the arguments by a reference. https://www.c-sharpcorner.com/UploadFile/ff2f08/ref-vs-out-keywords-in-C-Sharp/ https://www.c-sharpcorner.com/blogs/difference-between-ref-and-out-parameters https://www.dotnettricks.com/learn/csharp/difference-between-ref-and-out-parameters