JavaScript minute and second countdown timer implementation method_javascript skills

Remaining time:



<script> <br> /*Declare the function to be used by the main function*/ <br> var clock=new clock(); <br> /*Pointer to timer*/ <br> var timer; <br> window.onload=function(){ <br> /*The main function just calls the move method in the clock function every 50 seconds*/ <br> Timer=setInterval("clock.move()",50); <br> }  <br> function clock(){ <br> /*s is a variable in clock(), not a global variable like var, which represents the remaining seconds*/ <br> This.s=140; <br> This.move=function(){ <br> ​​​​/*Call the exchange function to convert seconds to minutes before output. Because exchange is not used in the main function window.onload, there is no need to declare it*/ <br>           document.getElementById("timer").innerHTML=exchange(this.s); <br> ​ ​ ​ /*Each time it is called, the remaining seconds will be decremented*/  <br> This.s=this.s-1; <br>                                                          /*If the time runs out, then a pop-up window will pop up, making the button unavailable, and stop calling move() in the clock function*/ <br> If(this.s<0){ <br /> alert("Time's up"); <br />                document.getElementById("go").disabled=true; <br />                                                                                               ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,                                                                                                                                                                                                                                           }  <br /> function exchange(time){ <br /> /*Javascript's division is floating point division, and Math.floor must be used to get the integer part*/ <br /> This.m=Math.floor(time/60); <br />               /*There is a remainder operation*/ <br /> This.s=(time`); <br /> This.text=this.m "minutes" this.s "seconds"; <br />                       /*Do not use this for the passed formal parameter time, and other variables used in this function must use this*/ <br />            return this.text;                                     } <br /> </script>


I hope this article will be helpful to everyone’s JavaScript programming design.