本文实例讲述了JS截取与分割字符串的常用方法。分享给大家供大家参考,具体如下:
JS截取字符串可使用 substring()或者slice()
函数:substring()
定义:substring(start,end)表示从start到end之间的字符串,包括start位置的字符但是不包括end位置的字符。
功能:字符串截取,比如想从"MinidxSearchEngine"中得到"Minidx"就要用到substring(0,6)
例子:
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函数:substr()
定义:substr(start,length)表示从start位置开始,截取length长度的字符串。
功能:字符串截取
例子:
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函数:split()
功能:使用一个指定的分隔符把一个字符串分割存储到数组
例子:
在本例中,我们将按照不同的方式来分割字符串:
<script type="text/javascript"> var str="How are you doing today?" document.write(str.split(" ") + "<br />") document.write(str.split("") + "<br />") document.write(str.split(" ",3)) </script>
输出:
How,are,you,doing,today? H,o,w, ,a,r,e, ,y,o,u, ,d,o,i,n,g, ,t,o,d,a,y,? How,are,you
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函数:John()
功能:使用您选择的分隔符将一个数组合并为一个字符串
例子:
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函数:indexOf()
功能:返回字符串中匹配子串的第一个字符的下标
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函数:lastIndexOf()
定义:lastIndexOf()方法返回从右向左出现某个字符或字符串的首个字符索引值(与indexOf相反)
功能:返回字符串索引值
例子:
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补充:substr 和 substring方法的区别
substr 方法
返回一个从指定位置开始的指定长度的子字符串。
stringvar.substr(start [, length ])
参数
stringvar
必选项。要提取子字符串的字符串文字或 String 对象。
start
必选项。所需的子字符串的起始位置。字符串中的第一个字符的索引为 0。
length
可选项。在返回的子字符串中应包括的字符个数。
说明
如果 length 为 0 或负数,将返回一个空字符串。如果没有指定该参数,则子字符串将延续到 stringvar 的最后。
示例
下面的示例演示了substr 方法的用法。
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substring 方法
返回位于 String 对象中指定位置的子字符串。
strVariable.substring(start, end)
"String Literal".substring(start, end)
参数
start
指明子字符串的起始位置,该索引从 0 开始起算。
end
指明子字符串的结束位置,该索引从 0 开始起算。
说明
substring 方法将返回一个包含从 start 到最后(不包含 end )的子字符串的字符串。
substring 方法使用 start 和 end 两者中的较小值作为子字符串的起始点。例如, strvar.substring(0, 3) 和 strvar.substring(3, 0) 将返回相同的子字符串。
如果 start 或 end 为 NaN 或者负数,那么将其替换为0。
子字符串的长度等于 start 和 end 之差的绝对值。例如,在 strvar.substring(0, 3) 和 strvar.substring(3, 0) 返回的子字符串的的长度是 3。
示例
下面的示例演示了 substring 方法的用法。
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希望本文所述对大家JavaScript程序设计有所帮助。
相关推荐:
JS截取与分割字符串方法:substring、substr、slice的区别
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