zoukankan      html  css  js  c++  java
  • js:方法2. 字符串

    String.charAt()/String.charCodeAt()###

    string.charAt(n); n:The index of the character that should be returned from string.

      var a = 'abc';
      a.charAt(2);   //=> 'c'
      a.charCodeAt(2);  //=>99
    

    String.concat()###

    string.concat(value, ...)

      var a = 'abc';
      a.concat('def'); //=> 'abcdef'
    

    String.fromCharCode()###

    String.fromCharCode(c1, c2, ...); c1, c2, ... Zero or more integers that specify the Unicode encodings of the characters in the string to be created.

    // Create the string "hello"
    var s = String.fromCharCode(104, 101, 108, 108, 111);
    

    String.indexOf() /String.lastIndexOf()###

    string.indexOf(substring) ; string.indexOf(substring, start)

     var a = 'abcabc';
      a.indexOf('b'); //=> 1
      a.indexOf('b', 1); //=> 1
      a.indexOf('b', 2); //=> 4
    

    String.match()###

    string.match(regexp)

    "1 plus 2 equals 3".match(/d+/g) // Returns ["1", "2", "3"]
    
    var url = /(w+)://([w.]+)/(S*)/;
    var text = "Visit my home page at http://www.isp.com/~david";
    var result = text.match(url);
    if (result != null) {
     var fullurl = result[0]; // Contains "http://www.isp.com/~david"
     var protocol = result[1]; // Contains "http"
     var host = result[2]; // Contains "www.isp.com"
     var path = result[3]; // Contains "~david"
    }
    

    String.replace()###

    string.replace(regexp, replacement)

    To ensure that the capitalization of the word “JavaScript” is correct:
    text.replace(/javascript/i, "JavaScript");
    
    To convert a single name from “Doe, John” format to “John Doe” format:
    name.replace(/(w+)s*,s*(w+)/, "$2 $1");
    
    To replace all double quotes with double back and forward single quotes:
    text.replace(/"([^"]*)"/g, "''$1''");
    
    To capitalize the first letter of all words in a string:
    text.replace(/w+/g, function(word) {
      return word.substring(0,1).toUpperCase() +
      word.substring(1);
    });
    

    String.search()###

    **string.search(regexp)###

    var s = "JavaScript is fun";
    s.search(/script/i) // Returns 4
    s.search(/a(.)a/) // Returns 1
    

    String.slice()###

    string.slice(start, end)

    var s = "abcdefg";
    s.slice(0,4) // Returns "abcd"
    s.slice(2,4) // Returns "cd"
    s.slice(4) // Returns "efg"
    s.slice(3,-1) // Returns "def"
    s.slice(3,-2) // Returns "de"
    s.slice(-3,-1) // Should return "ef"; returns "abcdef" in IE 4
    

    String.split()###

    string.split(delimiter, limit)

    "1:2:3:4:5".split(":"); // Returns ["1","2","3","4","5"]
    "|a|b|c|".split("|"); // Returns ["", "a", "b", "c", ""]
    
    var words = sentence.split(/s+/);
    
    "hello".split(""); // Returns ["h","e","l","l","o"]
    "hello".split("", 3); // Returns ["h","e","l"]
    
    var text = "hello <b>world</b>";
    text.split(/(<[^>]*>)/); // Returns ["hello ","<b>","world","</b>",""]
    

    String.substr()

    string.substr(start, length)

    var s = "abcdefg";
    s.substr(2,2); // Returns "cd"
    s.substr(3); // Returns "defg"
    s.substr(-3,2); // Should return "ef"; returns "ab" in IE 4
    

    String.substring()###

    string.substring(from, to)

      var a = 'abcabc';
      a.substring(1,3); //=> bc
    

    String.toLowerCase()/String.toLocaleLowerCase()/String.toUpperCase()/String.toLocaleUpperCase()#

    String.trim()

  • 相关阅读:
    《精通情绪》读书笔记
    绩效评估与绩效反馈
    数据分析报告格式zz
    学会谈判zz
    javascript中的双向绑定
    理解 DocumentFragment
    理解Object.defineProperty()
    Vue 改变数组中对象的属性不重新渲染View的解决方案
    ES6中Object.assign() 方法
    控制input输入框光标的位置
  • 原文地址:https://www.cnblogs.com/jinkspeng/p/4285918.html
Copyright © 2011-2022 走看看