C# 随机生成验证码

public static string GetCode()
{
string strList ="1234567890qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM";
Random rd = new Random();
string strResult = "";
for (int i = 0; i < 6; i++)
{
strResult += strList[rd.Next(0, strList.Length)];
}
return strResult;
}