1、String常用
下面说有错的地方其实没错,因为二进制里面不存在2这个字符啊,只有0和1!!!
2、String、Number互相转换
3、正则表达式
正则表达式中的特殊字符(同组内以逗号隔开):
引用
– ^, $, . – beginning, end of string, any one char ,
– \ – escape what would otherwise be a special character
– *, +, ? – 0 or more, 1 or more, 0 or 1 occurrences
– {n} {n } – exactly n n or more occurrences {n}, {n,} exactly n, n or more occurrences
– [] – grouping
– \s, \S – whitespace, non-whitespace
\w \W word char (letter or number) non word char – \w, \W – word char (letter or number), non-word char
正则表达式的选项:
引用
– /pattern/g – do global matching (find all matches, not just first one)
– /pattern/i – do case-insensitive matching
– /pattern/m – do multiline matching
本文源代码:
<!-- LCTestJS_String.html version: 2012_01_11 --> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>测试javascript 的string version: 2012_01_11</title> <style> h3 { color: #FFF; background-color: #09F; font-style: normal; font-weight: bold; } h4 { font-weight: bolder; color: #d00; background-color: #CCC; } </style> </head> <body> <h2>测试javascript 的string version: 2012_01_11</h2> <h3>String——常用的</h3> <h4> 单引号双引号均可 <p>用==判断两个字符串内容是否相同</p> </h4> <script type="text/javascript"> var strDoubleQuotes = "asdf"; var strSingleQuote = 'asdf'; var isEqual = strDoubleQuotes == strSingleQuote; document.write("<p>\"asdf\"=='asdf'?\t" + isEqual); </script> <h4>.length属性:字符串长度</h4> <script type="text/javascript"> document.write("<p>'asdf'.length=\t" + 'asdf'.length); </script> <h4>常用函数:类似java</h4> charAt, indexOf, lastIndexOf, substring, toLowerCase, toUpperCase <h4>html专用函数(非标准)</h4> <script type="text/javascript"> 'test'.bold().italics().fontcolor('red') document.write("<p>'test'.bold().italics().fontcolor('red')=" + 'test'.bold().italics().fontcolor('red')); </script> <h3>String,Number互相转换</h3> <h4> Number转String: .toFixed(num):按num保留小数点后的位数(四舍五入) <p>可以通过new String(arg)来明确声明为String类型(其他类型类似)</p> </h4> <script type="text/javascript"> document.write("<p>(1.236).toFixed(2)=\t" + (1.236).toFixed(2)); var n = 1.236; document.write("<p>(1.236).length=\t" + n.length); document.write("<p>(1.236).toFixed(2).length=\t" + (1.236).toFixed(2).length); document.write("<p>new String(1.236).length=\t" + new String(1.236).length); </script> <h4>String转Number;从第一个字母开始被忽略</h4> <script type="text/javascript"> var s = new String('1234ff'); document.write("<p>parseInt('12.34ff')=" + parseInt('12.34ff')); document.write("<p>parseInt('12.34ff', 2)=" + parseInt('12.34ff', 2) + "\t错了吧?"); document.write("<p>parseInt('12.34ff', 3)=" + parseInt('12.34ff', 3)); document.write("<p>parseInt('12.34ff', 4)=" + parseInt('12.34ff', 4)); document.write("<p>parseInt('12.34ff', 5)=" + parseInt('12.34ff', 5)); document.write("<p>----"); document.write("<p>parseFloat('12.34ff')=" + parseFloat('12.34ff')); </script> <h3>正则表达式</h3> <h4> 正则表达式: 用在两个斜杠(/表达式/)中间的式子,而非String来表示 <p>可用于函数:match, replace, search, split</p> </h4> <script type="text/javascript"> document.write("<p>'testABCDABCabc'.split(/A/)=" + 'testABCDABCabc'.split(/A/) + "\t结果是数组,直接输出以逗号隔开,可以自己用for语句输出"); //var splited='testABCDABCabc'.split(/A/); //for(var i=0;i<splited.length;i++){ // document.write("<p>"+splited[i]); //} document.write("<p>'testABCDABCabc'.split(/A/i)=" + 'testABCDABCabc'.split(/A/i) + "\t加个选项i,就变成大小写不敏感了"); </script> </body> </html>