javascript - Javascript 正则表达式匹配 iframe src

Question

如果我有两个 iframe，如何匹配没有 youtube src 的那个？

<iframe  src="http://googleads.g.doubleclick.net/pagead/ads?client=ca-feed-pub"></iframe>
<iframe  src="http://www.youtube.com/embed/Y4MnpzG5Sqc?wmode=opaque"></iframe>

Answer 1

您将所有数据都放在一个字符串中，可能包含多个标签？在这种情况下，您需要 1）在字符串中找到每个单独的 iframe，2）检查每个找到的 iframe，如果您需要删除它或不理会它。这是执行此操作的代码，其中注释显示了每个步骤的执行位置：

var string='<iframe  src="http://googleads.g.doubleclick.net/pagead/ads?client=ca-feed-pub"></iframe><iframe  src="http://www.youtube.com/embed/Y4MnpzG5Sqc?wmode=opaque"></iframe><iframe  src="http://googleads.g.doubleclick.net/pagead/ads?client=ca-feed-pub"></iframe><some_good_tag>TEST</some_good_tag><iframe  src="http://www.youtube.com/embed/Y4MnpzG5Sqc?wmode=opaque"></iframe>'

function filter_iframe(iframe_tag){
    // if iframe have youtube in it - return it back unchanged
    if(/src=".+youtube/.test(iframe_tag)){ return iframe_tag }
    // if not - replace it with empty string, effectively removing it
    return ''
}

// first, find each iframe in string and call function to check if you need to remove it
var filtered=string.replace(/(<iframe.*?>.*?<\/iframe>)/g, filter_iframe)

console.log(filtered)

Answer 2

var a='<iframe  src="http://googleads.g.doubleclick.net/pagead/ads?client=ca-feed-pub"></iframe><iframe  src="http://www.youtube.com/embed/Y4MnpzG5Sqc?wmode=opaque"></iframe><iframe  src="http://googleads.g.doubleclick.net/pagead/ads?client=ca-feed-pub"></iframe><iframe  src="http://www.youtube.com/"></iframe>'

var b=a.match(/(<iframe.+?<\/iframe>)/g),l=b.length,i=0;
for(i;i<l;i++){
  if(b[i].indexOf('youtube.com')>-1){a=a.replace(b[i],'')}
}​

http://jsfiddle.net/7ykXv/