将时间格式化为字符串

Question

I wrote this easy JS timer and i have problem with if for minutes, it still writing in first sec 00:01, second sec 000:02...... If you understand me. Please can you help me? Thank you

var sec = 0;
var min = 0;
var time;
function timer() {
  sec++;
  if (sec < 10) {
      sec = "0" + sec;
  }
   if (min < 10) {  //here is problem I think
       min = "0" + min;
   }

   if (sec == 60) {
       sec = 0;
       min++;
   }

   if (sec == 5) { //this is just a function test
       document.getElementById("myForm").submit();
   }
   document.getElementById("myTimer").innerHTML = min + ":" + sec;
}
function start() {
     time = setInterval("timer()", 1000);
}

Answer 1

Each time your function runs, it adds a zero to the beginning of min , which is a global variable. That's why it works the way it does.

You could use a temporary variable for holding the time as string.

 var sec = 0; var min = 0; var time; function timer() { sec++; var minStr = (min < 10) ? '0' + min : '' + min; var secStr = (sec < 10) ? '0' + sec : '' + sec; document.getElementById("myTimer").innerHTML = minStr + ":" + secStr; } function start() { time = setInterval("timer()", 1000); } start(); 

 <div id="myTimer"></div>