How to fire AJAX request Periodically

Question

lt meta http-equiv  Refresh  Content  5  gt    This script reloads or refresh the page after every 5 seconds  But I want to do it using jQuery and AJAX call  Is it possible

User · Answer

I tried the below code       function executeQuery         ajax       url   url path here       success  function data             do something with the return value here if you like               setTimeout executeQuery  5000      you could choose not to continue on failure         document  ready function          run the first time  all subsequent calls will take care of themselves   setTimeout executeQuery  5000         This didn t work as expected for the specified interval the page didn t load completely and the function was been called continuously  Its better to call setTimeout executeQuery  5000   outside executeQuery   in a separate function as below   function executeQuery         ajax       url   url path here       success  function data             do something with the return value here if you like               updateCall       function updateCall    setTimeout function   executeQuery     5000        document  ready function       executeQuery          This worked exactly as intended

User · Answer

As others have pointed out setInterval and setTimeout will do the trick  I wanted to highlight a bit more advanced technique that I learned from this excellent video by Paul Irish  http   paulirish com 2010 10-things-i-learned-from-the-jquery-source   For periodic tasks that might end up taking longer than the repeat interval  like an HTTP request on a slow connection  it s best not to use setInterval    If the first request hasn t completed and you start another one  you could end up in a situation where you have multiple requests that consume shared resources and starve each other  You can avoid this problem by waiting to schedule the next request until the last one has completed      Use a named immediately-invoked function expression   function worker         get  ajax test html   function data           Now that we ve completed the request schedule the next one          result   html data       setTimeout worker  5000                 For simplicity I used the success callback for scheduling  The down side of this is one failed request will stop updates  To avoid this you could use the complete callback instead    function worker         ajax       url   ajax test html        success  function data              result   html data              complete  function              Schedule the next request when the current one s complete       setTimeout worker  5000

User · Answer

Yes  you could use either the JavaScript setTimeout   method or setInterval   method to invoke the code that you would like to run   Here s how you might do it with setTimeout   function executeQuery         ajax       url   url path here       success  function data             do something with the return value here if you like               setTimeout executeQuery  5000      you could choose not to continue on failure         document  ready function          run the first time  all subsequent calls will take care of themselves   setTimeout executeQuery  5000

User · Answer

You can use setTimeout or setInterval   The difference is -  setTimeout triggers your function only once  and then you must set it again  setInterval keeps triggering expression again and again  unless you tell it to stop

[jquery] How to fire AJAX request Periodically?

Examples related to jquery

Examples related to ajax