C#中Split分割字符串的几种方法

1、用字符串分隔(正则)：
using System.Text.RegularExpressions;
string str="aaajsbbbjsccc";
string[] sArray=Regex.Split(str,"js",RegexOptions.IgnoreCase);
结果：
aaa
bbb
ccc

2、用多个字符来分隔：
string str="aaajbbbscccjdddseee";
string[] sArray=str.Split(new char[2] {'j','s'});
结果：
aaa
bbb
ccc
ddd
eee
3、用单个字符来分隔：
string s=abcdeabcdeabcde;
string[] sArray=s.Split('c') ;
结果:
ab
deab
deab
de

Split 的 separator 参数应该是char[] 或 string[]，不应是字符串。

Split分隔字符串时，如果分隔符为一个字符，一般情况下返回的字符数组长度是预期的。
但当分隔符为多个字符时，比如 str.Split("|||".ToCharArray()) ，返回的字符数组中可能会多出预期的长度，数组中会出现一些值为空的字符串元素。
可以采用正则表达式来分割：
string[] arr = Regex.Split( str, @"|||" ,RegexOptions.IgnoreCase );
注意：| 在正则表达式中是保留字符，需要用""转义。

分割文本域中以回车换行的例子：
string[] arr = s.Split(new string[] { "\r\n" }, StringSplitOptions.None)
string[] arr = Regex.Split( str , "\r\n" ,RegexOptions.IgnoreCase)

比较说明

String.Split 方法有6个重载函数：

程序代码

1. public string[] Split(params char[] separator)
2. public string[] Split(char[] separator, int count)
3. public string[] Split(char[] separator, StringSplitOptions options)
4. public string[] Split(string[] separator, StringSplitOptions options)
5. public string[] Split(char[] separator, int count, StringSplitOptions options)
6. public string[] Split(string[] separator, int count, StringSplitOptions options)

下边我们通过一些实例来说明下怎么使用(以下string words = "1,2.3,,4";)：

• 1. public string[] Split(params char[] separator)
     程序代码
     string[] split = words.Split(new Char[] { ',' });//返回:{"1","2.3","","4"}
     string[] split = words.Split(new Char[] { ',', '.' });//返回:{"1","2","3","","4"}
• 2. public string[] Split(char[] separator, int count)
     程序代码
     string[] split = words.Split(new Char[] { ',', '.' }, 2);//返回:{"1","2.3,,4"}
     string[] split = words.Split(new Char[] { ',', '.' }, 6);//返回:{"1","2","3","","4"}
• 3. public string[] Split(char[] separator, StringSplitOptions options)
     程序代码
     //返回:{"1","2","3","4"} 不保留空元素
     string[] split = words.Split(new Char[] { ',', '.' }, StringSplitOptions.RemoveEmptyEntries);
     //保留空元素
     string[] split = words.Split(new Char[] { ',', '.' }, StringSplitOptions.None);//返回:{"1","2","3","","4"}
• 4. public string[] Split(string[] separator, StringSplitOptions options)
     程序代码
     //返回:{"1","2","3","4"} 不保留空元素
     string[] split = words.Split(new string[] { ",", "." }, StringSplitOptions.RemoveEmptyEntries);
     //保留空元素
     string[] split = words.Split(new string[] { ",", "." }, StringSplitOptions.None);//返回:{"1","2","3","","4"}
• 5. public string[] Split(char[] separator, int count, StringSplitOptions options)
     程序代码
     //返回:{"1","2.3,,4"} 不保留空元素
     string[] split = words.Split(new Char[] { ',', '.' }, 2, StringSplitOptions.RemoveEmptyEntries);
     //保留空元素
     string[] split = words.Split(new Char[] { ',', '.' }, 6, StringSplitOptions.None);//返回:{"1","2","3","","4"}
• 6. public string[] Split(string[] separator, int count, StringSplitOptions options)
     程序代码
     //返回:{"1","2.3,,4"} 不保留空元素
     string[] split = words.Split(new string[] { ",", "." }, 2, StringSplitOptions.RemoveEmptyEntries);
     保留空元素
     string[] split = words.Split(new string[] { ",", "." }, 6, StringSplitOptions.None);//返回:{"1","2","3","","4"}