c#中字符串截取使用的方法

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         }