如何使用javascript查找和替换某些关键字之间的文本？

Question

For example i have this text

"!?vake 7EnEebjP8jXf JFyd5hpIVa6B  !?vake".

The starting and ending keyword is "!?vake" and i want to retrieve the encrypted content between the keywords,decrypt it and replace it.

The html code before replacing would be:

<span class="messageBody" data-ft="{&quot;type&quot;:3}">‎!?vake 7EnEebjP8jXf JFyd5hpIVa6B
Fu63LH23dAiB !?vake</span>

and after decrypting :

<span class="messageBody" data-ft="{&quot;type&quot;:3}">‎i am the decrypted text</span>

Replace should work in the whole html document without knowing the specific element the encrypted text is.

Answer 1

You can achieve this using RegExp. See a demo here : http://jsfiddle.net/diode/KVqJS/4/

var body = $("body").html();

var matched;
while ((matched = body.match(/!\?vake (.*?) !\?vake/))) {
    if(matched.length > 1){
        body = body.replace(/\!\?vake (.*) \!\?vake/, decode(matched[1]));
    }

}

$("body").html(body);

function decode(encoded) {
    return "decoded " + encoded;
}

Answer 2

You can use regex to find (and replace) the data.

Here is a quick and dirty JSFiddle: http://jsfiddle.net/z8rVc/1/

I'm sure someone will come up with a more elegant method, however.

Answer 3

You can use the following regex search and replace code in JS:

var a = "!?vake 7EnEebjP8jXf JFyd5hpIVa6B  !?vake";
var b = a.replace(/\!\?vake(.*)\!\?vake/g, '$1');
/// b contains your string between the keywords which you can decrypt as required.