setTimeout不在for循环内触发

Question

I have the following jquery code with setTimeout function to set a variable to false but it never works and the variable always remains to be true

      for( var ff = 0; ; ff++)
      {
        if( dif == 0){
          break;
        }
        if (locked){
          // locked = false;
          setTimeout( function(){ locked = false; },2000);
        }
        else{
          LeftKeyPressed();
          locked = true ;
          setTimeout( function(){ locked = false; },3000);
          dif--;
        }
      }

can anyone to help in how to set the locked variable to false after exactly two seconds from setting it to true.

Here's a fiddle of this issue .

Answer 1

Okey, since the requirements are what they are I dont know what exactly you want but this is closest I could manage to make: http://jsfiddle.net/db6gJ/

It calls method three times and gives you a change to do what you want to do when locked is false or true. Plus, it won't block the event loop (with that infinite for loop) so your site can make other tasks while timeOut call's are running.

javascript code also here:

var locked = true,
    timesMax = 3,
    timeCurrent = 0;

var inputLoop = function() {

    var delay = 2000;

    if(locked) {

        // Do something when locked is true
        console.log("locked is true!");

        locked = false;

    } else {

        // Do something when locked is false
        console.log("locked is false!");

        locked = true;
        delay = 3000;

    }

    timeCurrent++;

    // call again after delay, but call only 3 times
    if(timeCurrent < timesMax) {
        setTimeout(inputLoop, delay);
    }

};

// Launch it
inputLoop();

If you view your javascript console (in chrome: right mouse click -> inspect element -> console) it should print:

locked is true!
locked is false! 
locked is true! 

Also to be noted: your original code had alert('out'); when it's done, but to be honest, code will continue execution elsewhere while your "inputLoop" code is not doing anything else than waiting callback to be run and it's the way it should be.

If you wan't to know when it is called last time you could modify one of the previous lines to be:

// call again after delay, but call only 3 times
if(timeCurrent < timesMax) {
    setTimeout(inputLoop, delay);
} else { 
    // Last call in this method
    console.log('done!');
}