字符串比较

在我们写程序的时候进行两个字符串进行比较，经常是使用的是“==”和Epuals（）但是在.net中给我们提供了很多的方法，如：

system.String 对象中提供了4个方法，Compare、Compareordinal、CompareTo、Epuals方法，

下面进行举例；

#region Compare方法进行字符串比较\
               string str1 = "这是用COMPARE方法";
               string str2 = "这是用compare方法";
                int i  = string .Compare(str1,str2);
                Console.WriteLine("这是使用Compare( string str1, string str2的结果");
                DisplayResult(i);
              i = string .Compare(str1,str2,true );
              Console.WriteLine("这是使用Compare( string str1, string str2 ,bloo ignoreCase的结果");
              DisplayResult(i);
              i = string.Compare(str1, str2, StringComparison.CurrentCulture);
              Console.WriteLine("这是使用Compare( string str1, string str2 StringComparison.CurrentCulture的结果");
              DisplayResult(i);
           
                #endregion
                Console.ReadKey();
        }
        static void DisplayResult(int i)
        {
            if (i < 0)
            {
                Console.WriteLine("Str1>Str2");
            }
            else if (i == 0)
            {
                Console.WriteLine("Str1 == Str2");
            }
            else if (i>0)
            {
                Console.WriteLine("Str1>Str2");
            }
        }
      
    }

//使用Epulas();

   #region 使用Equlas()
                string str1 = "这是将要比较的字符串一";
                string str2 = "这是将要比较的字符串二";
                bool result;
                result = String.Equals(str1, str2);
                DisplayResult(result);
                result = str1.Equals(str2);
                DisplayResult(result);
                result = str1.Equals(str2, StringComparison.Ordinal);
                DisplayResult(result);
                result = string.Equals(str1, str2, StringComparison.Ordinal);
                DisplayResult(result);
                #endregion              

                     }
       public static void DisplayResult(int i)
       {
           if (i < 0)
          {
              Console.WriteLine("Str1>Str2");
           }
          else if (i == 0)
           {
                Console.WriteLine("Str1 == Str2");
            }
          else if (i>0)
          {
               Console.WriteLine("Str1>Str2");
           }
       }

//使用CompareTo比较字符串

 #region 使用CompareTo比较字符串
                string str1 = "这是将要比较的字符串一";
                string str2 = "这是将要比较的字符串二";
                int i = str1.CompareTo(str2);
                DisplayResult(i);
             
                #endregion
      public  static void DisplayResult(bool i)
    {
        if (i)
       {
           Console.WriteLine("这两个字符是相等的");
      }
        else if (i==false )
        {
            Console.WriteLine("这两个值不相等");
       }
    }
      
        public static void DisplayResult(int i)
        {
            if (i < 0)
            {
                Console.WriteLine("Str1>Str2");
            }
            else if (i == 0)
            {
                Console.WriteLine("Str1 == Str2");
            }
            else if (i > 0)
            {
                Console.WriteLine("Str1<Str2");
            }
        }