JavaScript中join()、splice()、slice()和split()函数用法示

join() 方法用于把数组中的所有元素放入一个字符串。

元素是通过指定的分隔符进行分隔的。

<script type="text/javascript"> var arr = new Array(3) arr[0] = "George" arr[1] = "John" arr[2] = "Thomas" document.write( arr.join() ) </script>

运行结果:

George,John,Thomas

<script type="text/javascript"> var arr = new Array(3) arr[0] = "George" arr[1] = "John" arr[2] = "Thomas" document.write( arr.join(".") ) </script>

运行结果:

George.John.Thomas

split()

split() 方法用于把一个字符串分割成字符串数组。

<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>

运行结果:

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

"2:3:4:5".split(":") //将返回["2", "3", "4", "5"] "|a|b|c".split("|") //将返回["", "a", "b", "c"] "hello".split("") //可返回 ["h", "e", "l", "l", "o"] "hello".split("", 3) //可返回 ["h", "e", "l"]

slice()

slice() 方法可从已有的数组中返回选定的元素。

<script type="text/javascript"> var arr = new Array(3) arr[0] = "George" arr[1] = "John" arr[2] = "Thomas" document.write(arr + "<br />") document.write( arr.slice(1) + "<br />") document.write(arr) </script>

运行结果:

George,John,Thomas
John,Thomas
George,John,Thomas

<script type="text/javascript"> var arr = new Array(6) arr[0] = "George" arr[1] = "John" arr[2] = "Thomas" arr[3] = "James" arr[4] = "Adrew" arr[5] = "Martin" document.write(arr + "<br />") document.write( arr.slice(2,4) + "<br />") document.write(arr) </script>

运行结果:

George,John,Thomas,James,Adrew,Martin
Thomas,James
George,John,Thomas,James,Adrew,Martin

splice()

splice() 方法向/从数组中添加/删除项目,然后返回被删除的项目。

注释:该方法会改变原始数组。

<script type="text/javascript"> var arr = new Array(6) arr[0] = "George" arr[1] = "John" arr[2] = "Thomas" arr[3] = "James" arr[4] = "Adrew" arr[5] = "Martin" document.write(arr + "<br />") arr.splice(2,0,"William") document.write(arr + "<br />") </script>

运行结果:

George,John,Thomas,James,Adrew,Martin
George,John,William,Thomas,James,Adrew,Martin

<script type="text/javascript"> var arr = new Array(6) arr[0] = "George" arr[1] = "John" arr[2] = "Thomas" arr[3] = "James" arr[4] = "Adrew" arr[5] = "Martin" document.write(arr + "<br />") arr.splice(2,1,"William") document.write(arr) </script>

运行结果:

George,John,Thomas,James,Adrew,Martin
George,John,William,James,Adrew,Martin

<script type="text/javascript"> var arr = new Array(6) arr[0] = "George" arr[1] = "John" arr[2] = "Thomas" arr[3] = "James" arr[4] = "Adrew" arr[5] = "Martin" document.write(arr + "<br />") arr.splice(2,3,"William") document.write(arr) </script>

运行结果:

George,John,Thomas,James,Adrew,Martin
George,John,William,Martin

感兴趣的朋友可以使用在线HTML/CSS/JavaScript代码运行工具测试运行一下文中所述代码。

更多关于JavaScript相关内容可查看本站专题:《JavaScript常用函数技巧汇总》、《JavaScript字符与字符串操作技巧总结》、《javascript面向对象入门教程》、《JavaScript错误与调试技巧总结》、《JavaScript数据结构与算法技巧总结》及《JavaScript数组操作技巧总结

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