Home > Article > Web Front-end > JS string traversal, interception, output, and calculation operations

JS string traversal, interception, output, and calculation operations

php中世界最好的语言Original: 2018-04-19 13:49:573261browse

This time I will bring you JS string traversal, interception, output, and calculation operations. What are the precautions for JS string traversal, interception, output, and calculation operations? The following is a practical case, let's take a look.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title>JS字符串</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
</head>
<body>
<script>
var str = "aaddaabbcdddefg";
console.log(str.charAt(7)); //b 没有返回空不是null
console.log(str.indexOf(&#39;p&#39;)); //1 没有返回-1
var obj = {};
for (var i = 0; i < str.length; i++) {
 var v = str.charAt(i);
 if (obj[v] && obj[v].value == v) {
  obj[v].count++;
 } else {
  obj[v] = {};
  obj[v].count = 1;
  obj[v].value = v;
 }
}
console.log(obj); //true
//obj = {a:object,b:object,c:object}
for (key in obj) {
 document.write(obj[key].value + &#39;=&#39; + obj[key].count + &#39; &#39;); // a=4 b=3 c=4 d=2 f=1 g=1 h=1
}
</script>
</body>
</html>

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!

JS string traversal, interception, output, and calculation operations

Related articles