calchash.cs

来自「C#高级编程第6版随书源代码 值得下载」· CS 代码 · 共 29 行

using System.Data.SqlTypes;
using System.Security.Cryptography;
using System.Text;
using Microsoft.SqlServer.Server;

public partial class UserDefinedFunctions
{
   [SqlFunction]
   public static SqlString CalcHash(SqlString value)
   {
      byte[] source;
      byte[] hash;

      source = ASCIIEncoding.ASCII.GetBytes(value.ToString());
      hash = new MD5CryptoServiceProvider().ComputeHash(source);

      StringBuilder output = new StringBuilder(hash.Length);

      for (int i = 0; i < hash.Length - 1; i++)
      {
         output.Append(hash[i].ToString("X2"));
      }

      return new SqlString(output.ToString());

   }
};