Many times it is required to execute a function many times after a
certain period of time. For example, you may want to refresh your screen
after a given time. Prototype provides a simple mechanism to implement
it using PeriodicalExecuter object.
The advantage provided by PeriodicalExecuter is that it shields you against multiple parallel executions of the callback function.
The advantage provided by PeriodicalExecuter is that it shields you against multiple parallel executions of the callback function.
Creating a PeriodicalExecuter
The constructor takes two arguments −- The callback function.
- The interval (in seconds) between executions.
Example
Following is the example which will pop up a dialogue box after every 5 seconds untill you will stop it by pressing "cancel' button.<html> <head> <title>Prototype examples</title> <script type = "text/javascript" src = "/javascript/prototype.js"></script> <script> function startExec() { new PeriodicalExecuter(function(pe) { if (!confirm('Want me to annoy you again later?')) pe.stop(); }, 5); } </script> </head> <body> <p>Click start button to start periodic executer:</p> <br /> <br /> <input type = "button" value = "start" onclick = "startExec();"/> </body> </html>
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