C#截取字符串的几种方式

1.根据单个分隔字符用Split截取

例如

string st="GT123_1";

string[] sArray=st.Split('_');

即可得到sArray[0]="GT123",sArray[1]="1";

//*****************************************///

string[] arr = str.Split("o");

这是一个具有语法错误的语句，Split 的 separator 参数应该是 char[] 或 string[]，不应是字符串。正确的示例：

string str = "technology";

char[] separator = { 'o' };

string[] arr = str.Split(separator);

////////////////////////////////////////////////////
2.利用多个字符来分隔字符串

例如

string str = "GTAZB_JiangjBen_123";

string[] sArray = str.Split(new char[2] { 'j', '_' });

foreach(string e in sArray)

{

Console.WriteLine(e);

}

得到sArray[0]="GTAZB",sArray[1]="Jiang",sArray[2]="Ben",sArray[3]="123";

3根据字符串或字符串组来截取字符串

例如

string str = "GTAZB_JiangjBen_123";

string[] sArray = str.Split( new string[]{"Ji","jB"}, StringSplitOptions.RemoveEmptyEntries);

foreach(string e in sArray)

{

Console.WriteLine(e);

}

得到sArray[0]="GTAZB_",sArray[1]="ang",sArray[2]="en_123";

4提取字符串中的第i个字符开始的长度为j的字符串；

例如

string str = "GTAZB_JiangjBen_123";

int start=3,length=8;

Console.WriteLine(str.Substring(start-1, length));

输出得到AZB_Jian。

5提取字符串中右数长度为i的字符串

string str = "GTAZB_JiangjBen_123";

string tSt;

int i=5;

tSt = str.Substring(str.Length - i);

Console.WriteLine(tSt);

输出n_123;

6替换字符串中的特定字符串

string str = "GTAZB_JiangjBen_123";

string tSt;

tSt = str.Replace("123","321");

Console.WriteLine(tSt);

输出GTAZB_JiangjBen_321

7删除字符串中的特定字符串Jiangj (JS方法 replace )

string str = "GTAZB_JiangjBen_123";

string tSt;

tSt = str.Replace("Jiangj","");

Console.WriteLine(tSt);

输出GTAZB_Ben_123

8删除指定位置(第i个)的指定长度（length）的字符串

string str = "GTAZB_JiangjBen_123";

int i=5,length=8;

str=str.remove(i,length);

console.writeline(str);

输出GTAZBen_123。

另附C# Split用法：

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
string[] split = words.Split(new Char[] { ',', '.' }, StringSplitOptions.RemoveEmptyEntries);//返回:{"1","2","3","4"} 不保留空元素

string[] split = words.Split(new Char[] { ',', '.' }, StringSplitOptions.None);//返回:{"1","2","3","","4"} 保留空元素

4. public string[] Split(string[] separator, StringSplitOptions options)

程序代码
string[] split = words.Split(new string[] { ",", "." }, StringSplitOptions.RemoveEmptyEntries);//返回:{"1","2","3","4"} 不保留空元素

string[] split = words.Split(new string[] { ",", "." }, StringSplitOptions.None);//返回:{"1","2","3","","4"} 保留空元素

5. public string[] Split(char[] separator, int count, StringSplitOptions options)

程序代码
string[] split = words.Split(new Char[] { ',', '.' }, 2, StringSplitOptions.RemoveEmptyEntries);//返回:{"1","2.3,,4"} 不保留空元素

string[] split = words.Split(new Char[] { ',', '.' }, 6, StringSplitOptions.None);//返回:{"1","2","3","","4"} 保留空元素

6. public string[] Split(string[] separator, int count, StringSplitOptions options)

程序代码
string[] split = words.Split(new string[] { ",", "." }, 2, StringSplitOptions.RemoveEmptyEntries);//返回:{"1","2.3,,4"} 不保留空元素

string[] split = words.Split(new string[] { ",", "." }, 6, StringSplitOptions.None);//返回:{"1","2","3","","4"} 保留空元素

需要注意的是没有重载函数public string[] Split(string[] separator)，所以我们不能像VB.NET那样使用words.Split(",")，而只能使用words.Split(','）