1 var pattern=/[a-z]+/; //这里使用了贪婪模式,
2 var str='abcdefg';
3 alert(str.replace(pattern,'1')); //所有的字符串变成了1
4
5 var pattern=/[a-z]+?/; //这里使用了惰性模式,
6 var str='abcdefg';
7 alert(str.replace(pattern,'1')); //只有第一个字符变成了1,后面没有匹配
8
9 var pattern=/[a-z]+?/; //开启全局,并且使用惰性模式,
10 var str='abcdefg';
11 alert(str.replace(pattern,'1')); //每一个字母替换成了1
12
13 var pattern=/6(.*)6/; //使用了贪婪模式,
14 var str='6google6 6google6 6google6'; //匹配到了google6 6google6 6google
15 document.write(str.replace(pattern,'<strong>$1<strong>')); //结果:<strong>google6 6google6 6google<strong>
16
17 var pattern=/6(.*?)6/; //使用了惰性模式,
18 var str='6google6 6google6 6google6';
19 document.write(str.replace(pattern,'<strong>$1<strong>')); //结果:<strong>google<strong> 6google6 6google6
20
21 var pattern=/6(.*?)6/g; //使用了惰性模式,开启全局
22 var str='6google6 6google6 6google6';
23 document.write(str.replace(pattern,'<strong>$1<strong>'));
24 //结果:<strong>google<strong> <strong>google<strong> <strong>google<strong>
25 //结果正确
26
27 var pattern=/6([^6]*)6/g; //另一种惰性,屏蔽了6的匹配,也就是两边的包含字符
28 var str='6google6 6google6 6google6';
29 document.write(str.replace(pattern,'<strong>$1<strong>'));