JavaScript (ヘッダに置く)
myButton = 0;
function myWatch(flug){
if (myButton==0){
Start=new Date();
myButton = 1;
document.myForm.myFormButton.value = "Stop!";
myInterval=setInterval("myWatch(1)",1);
} else {
if (flug==0){
myButton = 0;
document.myForm.myFormButton.value = "Start";
clearInterval( myInterval );
}
Stop=new Date();
T = Stop.getTime() - Start.getTime();
H = Math.floor(T/(60*60*1000));
T = T-(H*60*60*1000);
M = Math.floor(T/(60*1000));
T = T-(M*60*1000);
S = Math.floor(T/1000);
Ms = T%1000;
document.myForm.myClick.value = H+":"+M+":"+S+":"+Ms;
}
}
HTML
<form name="myForm" action="#">
<div>
<input type="text" size="20" name="myClick">
<input type="button" value="Start" name="myFormButton"
onclick="myWatch(0)">
</div>
</form>