Window.setInterval. Summary Calls a function or executes a code snippet repeatedly, with a fixed time delay between each call to that function. Syntax var intervalID = window.setInterval(func, delay[, param1, param2, ...]); var intervalID = window.setInterval(code, delay); intervalID is a unique interval ID you can pass to clearInterval(). func is the function you want to be called repeatedly. code in the alternate syntax, is a string of code you want to be executed repeatedly (using this syntax is not recommended for the same reasons as using eval()) delay is the number of milliseconds (thousandths of a second) that the setInterval() function should wait before each call to func. Note that passing additional parameters to the function in the first syntax does not work in Internet Explorer. Note: Prior to Gecko 13 (Firefox 13.0 / Thunderbird 13.0 / SeaMonkey 2.10), Gecko passed an extra parameter to the callback routine, indicating the "actual lateness" of the timeout in milliseconds.
Examples Inactive tabs. Javascript Tutorial - Using setInterval and setTimeout. In javascript, the two functions setInterval and setTimeout can be extremely useful and important, but using either of them in complex ways can be a confusing ordeal. In this tutorial, I'm going to try and show the range of possibilities, from the very simple, to the complex, to the 'why oh why is it working like this!?
'. So lets start out with the extremely simple - what do the setInterval and setTimeout functions do? They are both functions attached to the window object of a web page, and they allow, in a very crude manner, a sort of 'thread-like' control. The setTimeout call lets you tell the browser to execute a javascript call after a certain time has passed. It takes two arguments - what to execute, and how long to wait (in milliseconds).
SetTimeout("alert('hi! ') This call will execute the code alert('hi! ') setInterval("alert('hi! ') This call will execute the code alert('hi'); every 500 milliseconds from now until the the page it is loaded on is closed. function foo(){ alert("hi! ") JavaScript’s setTimeout and how to use it with your methods » Klevo blog. Update: My solution does not work in IE. Look at this article for comprehensive info. While working on Chatcreator’s Chatbox I run into problems with JavaScript’s setTimeout function. I would like to write down what I learned. It may save you some time, next time you’ll need to use this function. Shortly about setTimeout setTimeout is a simple JavaScript function used to repeatedly call some function after a specified amount of time. SetTimeout(functionToCall, time, param1, param2, ....) setTimeout('functionToCall()', time, ...)The optional parameters can be used to pass any number of parameters to our functionToCall.
Where’s the catch? Everything works as expected until you try to call a method inside your ‘class’ (there are no real classes in JavaScript). SetTimeout(this.methodToCall, time);Passing a string representation instead of reference doesn’t work either. The solution I found the solution after a while searching in Google Code Search. Javascript - Passing Multiple Parameters through setTimeout - Richard Castera. Creating Accurate Timers in JavaScript. Asynchronous timers are the cornerstone of all time-based processes in JavaScript. From obvious things like clocks and stopwatches, to visual effects and animation, to the synchronised delays that are vital to the usability of dropdown menus. But the problem with JavaScript timers is that they’re not very accurate. We couldn’t make a stopwatch just by incrementing x, because it wouldn’t stay in time: var time = 0, elapsed = '0.0'; window.setInterval(function() { time += 100; elapsed = Math.floor(time / 100) / 10; if(Math.round(elapsed) == elapsed) { elapsed += '.0'; } document.title = elapsed; }, 100); Web browsers, like all applications, take turns for a piece of CPU time, and the time they have to wait will vary, depending on the load.
This is what causes the latency in asynchronous timers — a 200ms timer may actually take 202ms, or 204, and this will gradually send the stopwatch out of time. Can’t beat the system The demo has three examples: Go with the flow. Multiple setTimeouts ? [Archive]