C# generate unique user ID

Ideas

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Use fixedCLientID_（用于分别出这是用户id）现在的时间(设备信息+用户名)Md5转换随机数（确保唯一） string ++ .

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Code

Parameters that need to be entered

length: How many digits of random numbers are used to generate.

UserName: The user's username.

 public string CreateRandomCode(int length, string UserName)  //随机生成客户端ID
        {
            string LocalTime = DateTime.Now.ToShortTimeString();//获取时间
            LocalTime = LocalTime.Replace(":", "");//将符号去掉

            string list = "qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM1234567890";//list中存放着随机的元素
            string UserhostName = Dns.GetHostName() + UserName;//获取主机名和用户名
            MD5 mD5 = new MD5CryptoServiceProvider();//创建Md5实例
            UserhostName = BitConverter.ToString(mD5.ComputeHash(Encoding.Default.GetBytes(UserhostName)), 4, 4);//生成多长的值，可以自行调参
            UserhostName = UserhostName.Replace("-", "");//连接

            Random random = new Random();//创建实例
            string code = "";   //随机数
            for (int i = 0; i < length; i++)   //循环得到一个伪随机的数
            {
                code += list[random.Next(0, list.Length - 1)];
            }

            string ClientID = "Client_"+ LocalTime + UserhostName + code;//生成客户ID

            return ClientID;
        }
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call method

        private void button1_Click(object sender, EventArgs e)//C#的Button按钮
        {
            textBox1.Text= CreateRandomCode(3, textBox2.Text);//最长随机数3位

        }
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achieve effect

 

 

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expand

Because C# comes with the MD5 class, it is very convenient to use. The following is the usage of the method used this time.

MD5 class method (from official documentation)

ComputeHash(Byte[], Int32, Int32)

Calculates the hash value of the specified range of the specified byte array.

public byte[] ComputeHash (byte[] buffer, int offset, int count);

parameter

• buffer

The input whose hash code is to be calculated.

• offset

The offset in the byte array from which data is used.

• count

The number of bytes used as data in the array.