Problem of string combinations via loop code [duplicate]

I have a code for string combinations via loop code.

I made a code to create a four-digit random string. And I want to create a license key by repeating my code 8 times.

e.g. D1c4-SXsc-DJod-10cK-Cm3q-m4N8-10x1-3cCd)  

My code able to accurately create random strings. but, when the code call from the loop code, result of the code repeat the same string.

e.g. D1c4-D1c4-D1c4-D1c4-D1c4-D1c4-D1c4-D1c4  

However, if I add a code to check the string through the message box, the exact result will be displayed.

This is my code :

private string Get_Product_Key()  {      string product_key = "";        for (int index = 0; index <= 7; index++)      {          var key = Get_Random_String(4);          product_key = product_key + key + '-';            //MessageBox.Show(key);      }      return product_key;  }    private string Get_Random_String(int length)  {      Random random = new Random();      string input = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";        var chars = Enumerable.Range(0, length).Select(x => input[random.Next(0, input.Length)]);        return new string(chars.ToArray());  }  

Please give me some advice.

https://stackoverflow.com/questions/66947756/problem-of-string-combinations-via-loop-code April 05, 2021 at 10:58AM