using System;

using System.Web.Security;

​

public class Hello{

 public static void Main(){

     for(var i=0;i<10;i++){

        Console.WriteLine(GenerateAuthKey(64));

     }

 }

 public static string GenerateAuthKey(int len){

    var key = Membership.GeneratePassword(len,0);

    var ex = "!@#$%^&*()+=[{]};:<>|./?"; //_-

    var cs = ex.ToCharArray();

    for(var i=0;i<ex.Length;i++){

        var x = cs[i].ToString();

        var y = Math.Abs(ex.IndexOf(x)).ToString(); 

        key = key.Replace(x,y.Substring(y.Length-1,1));

    }

    return key;

 }

}