在某一点之前替换所有文本

Question

$(function(){
    var alphabet = "ABCDEFGHIJKLMNOPQRSTUVEXYZ";
    var replaced = alphabet.replace(/(M).+$/,'');
    $('body').text(replaced);
});

我怎样才能在相反的方向上取而代之,取而代之的M呢？

Answer 1

使用/^.+M/表达式:

$(function() {
    var alphabet = "ABCDEFGHIJKLMNOPQRSTUVEXYZ";
    var replaced = alphabet.replace(/^.+M/,'');
    $('body').text(replaced);
});

演示: http ://jsfiddle.net/kbZhU/1/

更快的选择是使用indexOf和substring方法:

$(function(){
    var alphabet = "ABCDEFGHIJKLMNOPQRSTUVEXYZ";
    var replaced = alphabet.substring(alphabet.indexOf("M") + 1);
    $('body').text(replaced);
});

DEMO: http://jsfiddle.net/kbZhU/2/