?????? ???
?? ???(??: ?? ???, ?? ???? regex, regexp ?? RE? ???)? ?? ???? ???? ?? ?? ??? ??? ??? ??? ?? ??? ???? ??????.
??? ?? ? ??? ??? ??? ? ?? ?? ?????.
?? ????? ??????
?? ???? ??? ??? ??? ?? ?????.
????? ???? ??? ? ?? ??? ???? ????? ??? ??? ? ????.
?? ???? ??? ??? ?? ?? ? ??? ??? ?? ????.
???? ?? ??? ?? ? ??? ??? ??? ??? ? ????.
??
/pattern/modifiers;
?:
var patt = /phpl/i
?? ??:
/php/i? ?? ??????.
php? ?????(??? ???).
i? ??????(??? ????? ???? ????).
??? ??? ??
JavaScript?? ???? ????? ? ?? ??? ???, search() ? ???()? ?????.
search() ???? ????? ??? ?? ???? ????? ?? ???? ???? ?? ???? ???? ?? ???? ?? ??? ???? ? ?????.
replace() ???? ???? ?? ??? ?? ??? ???? ???? ???? ?? ???? ??? ? ?????.
search() ???? ???? ?????
?
????? ???? ?? "php.cn" ???? ????? ???? ?????.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>PHP中文網(wǎng)(php.cn)</title>
</head>
<body>
<p>搜索字符串 "php.cn", 并顯示匹配的起始位置：</p>
<button onclick="myFunction()">點(diǎn)我</button>
<p id="demo"></p>
<script>
function myFunction() {
var str = "Visit php.cn!";
var n = str.search(/php.cn/i);
document.getElementById("demo").innerHTML = n;
}
</script>
</body>
</html>????? ???? ??? ???.
search() ???? ???? ?????.
?? ???? ???? ????? ??? ? ????. . ??? ????? ?? ????? ?????:
Example
????? "php.cn"? ?? ???? ?????:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>PHP中文網(wǎng)(php.cn)</title>
</head>
<body>
<p>搜索字符串 "php.cn", 并顯示匹配的起始位置：</p>
<button onclick="myFunction()">點(diǎn)我</button>
<p id="demo"></p>
<script>
function myFunction() {
var str = "Visit php.cn!";
var n = str.search("php.cn");
document.getElementById("demo").innerHTML = n;
}
</script>
</body>
</html>????? ???? ??? ???
replace() ??? ???? ????? Expression
Example
???? ????? ???? ?? ???? Microsoft? php.cn?? ????.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>PHP中文網(wǎng)(php.cn)</title>
</head>
<body>
<p>替換 "microsoft" 為 "php.cn" :</p>
<button onclick="myFunction()">點(diǎn)我</button>
<p id="demo">請(qǐng)?jiān)L問 Microsoft!</p>
<script>
function myFunction() {
var str = document.getElementById("demo").innerHTML;
var txt = str.replace(/microsoft/i,"php.cn");
document.getElementById("demo").innerHTML = txt;
}
</script>
</body>
</html>????? ???? ??? ???
replace() ??? ???
replace() ???? ???? ???? ????? ?????.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>PHP中文網(wǎng)(php.cn)</title>
</head>
<body>
<p>替換 "Microsoft" 為 "php.cn" :</p>
<button onclick="myFunction()">點(diǎn)我</button>
<p id="demo">請(qǐng)?jiān)L問 Microsoft!</p>
<script>
function myFunction() {
var str = document.getElementById("demo").innerHTML;
var txt = str.replace("Microsoft","php.cn");
document.getElementById("demo").innerHTML = txt;
}
</script>
</body>
</html>????? ???? ??? ???.
?:
?? ??? ????? ? ????? ?? ??? ? ????. ??? ????).
???? ?? ??? ?? ???? ????(?: ?/???? ???? ??).
?? ??? ???
???? ?? ???? ????? ??? ? ????.
| ??? | ?? |
|---|---|
| i | ???? ??- ??? ??. |
| g | ?? ??? ?????(? ?? ?? ??? ?? ? ???? ?? ?? ?? ?? ??). |
| m | ?? ? ??? ?????. |
?? ??? ??
???? ??? ??? ?? ? ?????.
| Expression | Description |
|---|---|
| [abc] | ??? ?? ??? ?? ??? ????. |
| [0-9] | 0?? 9??? ??? ????. |
| (x|y) | |? ??? ??? ????. |
?? ??? ??? ??? ?? ?????.
| ?? ?? | Description |
|---|---|
| d | ??? ????. |
| s | ?? ??? ????. |
| b | ?? ??? ??????. |
| uxxxx | 16?? xxxx? ??? ???? ??? ????. |
???:
| Quantifier | ?? |
|---|---|
| n+ | ? ?? ??? n? ???? ?? ???? ?????. |
| n* | ? 0? ??? n? ???? ?? ???? ?????. |
| n? | ? 0? ?? 1?? n? ???? ?? ???? ?????. |
RegExp ?? ??
JavaScript?? RegExp ??? ?? ??? ??? ???? ?? ??? ?????.
test() ??
test() ???? ??? ??????.
test() ???? ???? ?? ??? ????? ???? ? ?????. ???? ???? ???? ???? ??? true? ???? ??? ??? false? ?????.
?? ?? ????? ?? "e"? ???? ? ?????.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>PHP中文網(wǎng)（php.cn）</title>
</head>
<body>
<script>
var patt1=new RegExp("e");
document.write(patt1.test("The best things in life are free"));
</script>
</body>
</html>????? ???? ??? ???
?? ? ?? ??? ??? ??? ??? ??? ????.
/e/ .test("???? ?? ?? ?? ?????!")
exec() ??
exec() ???? ?? ??? ??????. .
exec() ???? ????? ??? ?? ??? ???? ? ?????.
? ??? ???? ??? ???? ??? ?????. ???? ??? ??? ?? ?? null???.
?? ?? ????? ?? "e"? ???? ? ?????.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>PHP中文網(wǎng)(php.cn)</title>
</head>
<body>
<script>
var patt1=new RegExp("e");
document.write(patt1.exec("The best things in life are free"));
</script>
</body>
</html>????? ???? ??? ???
