有没有办法告诉网络浏览器继续“卡住”脚本？

Question

I have created this recursive script that checks what address your on, and then checks in another file hierarchy if that folder your in are in, also exists on that place. Like for example say you're on somerandomsite.com/example/folder/folder1/folder1_1 and then you might want to redirect the user to somerandomsite.com/ another /example/folder/folder1/folder1_1 if that folder exists, otherwise just redirect him to somerandomsite.com/another (of course I have som special cases as well, like if folder/folder1/ exists but not folder/folder1/folder1_1, then redirect to somerandomsite.com/ another /example/folder/folder1/ etc.

Now to my problem, I have a real slow recursive implementation, and say that there are 50 folders in folder "example", 100 folders in folder, another folders in folder1, and last 100 folders the last level, then my implementation takes long time to "match" all the names.

So some browsers display an error message that "some script has stopped working" since it is taking to long to execute. So my question is if there is some way to tell the browsers to let the script finish?

You can find the code for the script here .

And for those who wounder how I perform the directory searches is that im creating xmlhttprequests to folders, and get a html version displaying all the folders, and then do a simple pattern match for each folder level. In the example above I do 4 xmlhttpRequests,

One to somerandomsite.com, patternmatch for "example"

One to somerandomsite.com/example/ patternmatch for "folder"

One to somerandomsite.com/example/folder/ patternmatch for "folder1"

One to somerandomsite.com/example/folder/folder1/ patternmatch for "folder1_1"

Answer 1

No. That feature is designed explicitly for slow scripts, as you admitted yours is. It's up to the user to decide whether to continue. If there was an escape hatch all sorts of harmful scripts would use it.

Answer 2

I doubt that would occur with AJAX calls, since there is no actual script running while the request is made. Are you positive you don't have any infinite loops in your code.

Oh, there is a problem with your code:

handleXML is your event handler for readystatechange , and it calls checkState which spawns a timeout to call itself every second. So every time the state changes you spawn another repeating checkState. checkState which spawns a timeout to call itself every second. So every time the state changes you spawn another repeating checkState.

You don't need checkState to call itself, because handleXML already calls it and is called every time the state changes anyways. Also if the status returned isn't 200 the checkState will call itself forever. I think browsers will be much happier with you if you change your checkState function to:

var checkState = function(xmlhttp, callback) {
    if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
        callback();
};

Answer 3

Good lord, do that on the server. You're already "getting httprequest lists of directories within a directory" - just do the whole thing on the server.

Answer 4

No. Look into using Web Workers to get the job done. But be wary of compatibility with older browsers.

Answer 5

The script is doing that because to much is happening at once.

Wait to start a new xmlhttprequest until the previous one has finished.

Other then using a faster browser, you can't force a script to keep running.