Detailed explanation of replace function usage

This time I will bring you a detailed explanation of the use of the replace function. What are the precautions when using the replace function. The following is a practical case, let's take a look.

The syntax of the replace method is: stringObj.replace(rgExp, replaceText) where stringObj is a string( string), reExp can be a regular expression object (RegExp) or a string (string), replaceText is to replace the found string. .

Without further ado, I will post the code directly for you. The specific code is as follows:

 <script>
var str = "a1ba2b";
var reg = /a.b/g;
str = str.replace(reg,function(a,b){
 console.log(a);
 console.log(b);
 return b == 0 ? a.replace("a","0") : a.replace("b","3");
});
console.log(str);
/*
输出结果为：
a1b
0//第一次匹配到a1b，将a置为0.
a2b
3//第二次匹配到a2b，将b置为3.
01ba23//返回经过修改后的字符串
*/
/*
function（a,b,c）一共可以传入3个参数，第一个为匹配的字符串，第二个为匹配字符串的起始位置，
第三个为调用replace方法的字符串本身。可以缺省c或b、c。
*/
</script>

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the PHP Chinese website!

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