转自：http://www.cnblogs.com/Deckard/archive/2009/06/03/1495452.html

C#截取字符串(String.Substring方法)

String.Substring 方法

名称 说明  String.Substring (Int32)         从此实例检索子字符串。子字符串从指定的字符位置开始。  String.Substring (Int32, Int32) 从此实例检索子字符串。子字符串从指定的字符位置开始且具有指定的长度。

举例如下：

using System; using System.Collections.Generic; using System.Text;

namespace ConsoleApplication1 {     class Program     {         static void Main(string[] args)         {             string s = "Hello C# World!";             //s1为从s中截取的位置为3的字符以后的字符子串,3表示子字符串的起始字符位置             string s1=s.Substring(3);             Console.WriteLine(s1);             //s2为从s中截取的位置为6的字符开始长度为2的字符串，6表示子字符的起始字符位置，2表示子字符长度             string s2 = s.Substring(6, 2);             Console.WriteLine(s2);         }     } } 结果如下：

lo C# World!

C#

随即在附上一个C#截取字符串函数

public string getString(string RawString, Int32 Length)      {          if (RawString.Length <= Length)          {              return RawString;          }          else          {              for (Int32 i = RawString.Length - 1; i >= 0; i--)              {                  if (System.Text.Encoding.GetEncoding("GB2312").GetByteCount(RawString.Substring(0, i)) < Length)                  {                      return RawString.Substring(0, i) + "...";                  }              }              return "...";          }      }

 

1/** <summary>  2        /// 截取字符串，不限制字符串长度  3        /// </summary>  4        /// <param name="str">待截取的字符串</param> 5        /// <param name="len">每行的长度，多于这个长度自动换行</param>  6        /// <returns></returns>  7        public string CutStr(string str,int len)  8        {    string s="";  9              10            for(int i=0;i<str.Length ;i++)  11            {  12                int r= i% len;  13                int last =(str.Length/len)*len;  14                if (i!=0 && i<=last)  15                {  16                      17                    if( r==0)  18                    {  19                        s+=str.Substring(i-len,len)+"<br>"; 20                    }  21                          22                }  23                else if (i>last)  24                {  25                    s+=str.Substring(i-1) ;  26                    break;  27                }  28                  29            }  30              31            return s;  32              33        }  34  35  36        /** <summary>  37        /// 截取字符串并限制字符串长度，多于给定的长度＋。。。  38        /// </summary>  39        /// <param name="str">待截取的字符串</param>  40        /// <param name="len">每行的长度，多于这个长度自动换行</param>  41        /// <param name="max">输出字符串最大的长度</param>  42        /// <returns></returns>  43        public string CutStr(string str,int len,int max)  44        {  45            string s="";  46            string sheng="";  47            if (str.Length >max)  48            {  49                str=str.Substring(0,max) ;  50                sheng="";  51            }  52            for(int i=0;i<str.Length ;i++)  53            {  54                int r= i% len;  55                int last =(str.Length/len)*len;  56                if (i!=0 && i<=last)  57                {  58                      59                    if( r==0)  60                    {  61                        s+=str.Substring(i-len,len)+"<br>"; 62                    }  63                          64                }  65                else if (i>last)  66                {  67                    s+=str.Substring(i-1) ;  68                    break;  69                }  70                  71            }  72              73            return s+sheng;  74              75        }