Detailed description of code cases in which C # bulk generation random passwords must contain numbers and letters and encrypted with an encryption algorithm

This article mainly describes the C # batch generation random password must contain numbers and letters and encryption algorithm encryption, need to refer to the friend

Requirements:

Passwords must contain numbers and letters

Ideas:

1. List numbers and characters. Composition string: Chars

2. Use Randrom. Next (int i) returns a nonnegative random number that is less than the specified maximum value.

3. Randomly take a random number A, not less than chars length, and take the chars character of the string.

4. Loop 8 times, get 8-digit password

5. Loop n times to get the password in bulk.

The code implements the following main function:

static void Main (string[] args)    {      string chars = " 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZ ";      Random randrom = new Random ((int) DateTime.Now.Ticks);      String path1 = @ "C:\Users\lenovo\Desktop\pws.txt";      for (int j = 0; J < 10000;j++)      {        string str = "";        for (int i = 0; i < 8; i++)        {          str + = Chars[randrom. Next (chars. Length)];//randrom. Next (int i) returns a nonnegative random number that is less than the specified maximum value        }        if (Isnumber (str))//Determines whether it is all digital          continue;        if (Isletter (str))//judgment is all the letter          continue;        File.appendalltext (path1, str);        string PWS = Md5 (str,32),//MD5 encryption        file.appendalltext (path1, "," + PWS + "\ r \ n");      }      Console.WriteLine ("OK");      Console.read ();    }

Skillfully use String.Trim function, judge whether all is the number, all is the letter.

Description: String.Trim removes leading and trailing white space characters from a string object.

Returns: a copy of a string in which all whitespace characters are removed from the beginning and end of the string.

There is an overload:string.Trim(params char[] trimChars)

Removes all leading and trailing occurrences of a set of characters specified in an array from the current System.String object

TrimChars: Array of characters to delete

method to implement the following code:

Determines whether the digital    static bool Isnumber (String str)    {      if (str) is all. Trim ("0123456789". ToCharArray ()) = = "")        return true;      return false;    }    Determines whether all the letters are    static bool Isletter (String str)    {      if (str). Trim ("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz". ToCharArray ()) = = "")        return true;      return false;    }

With MD5 encryption, the algorithm code is implemented as follows:

<summary>    //MD5 encryption    ///</summary>//<param name= "str" > Cryptographic characters </param>/ <param name= "code" > Encryption bits 16/32</param>///    <returns></returns> public    static String Md5 (string str, int code)    {      string strencrypt = string. Empty;      MD5 MD5 = new MD5CryptoServiceProvider ();      byte[] Fromdata = encoding.getencoding ("GB2312"). GetBytes (str);      byte[] Targetdata = Md5.computehash (fromdata);      for (int i = 0; i < targetdata.length; i++)      {        Strencrypt + = Targetdata[i]. ToString ("X2");      }      if (code = =)      {        Strencrypt = strencrypt.substring (8, +);      }      return strencrypt;    }

Generate bulk passwords, and encrypted passwords such as: