Question

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<script src="jquery-1.10.2.js"></script>
<script language="JavaScript">
    var hoursleft = 0;
    var minutesleft = 0; // you can change these values to any value greater than 0
    var secondsleft = 0;
    var millisecondsleft = 0;
    var finishedtext = "Your Time is Up Question Switch to Others!"; // text that appears when the countdown reaches 0
    end = new Date();

    //end.setHours(end.getHours()+hoursleft);
    end.setMinutes(end.getMinutes() + minutesleft);
    end.setSeconds(end.getSeconds() + secondsleft);
    end.setMilliseconds(end.getMilliseconds() + millisecondsleft);

    function cd() {

        now = new Date();
        diff = end - now;
        diff = new Date(diff);
        var msec = diff.getMilliseconds();
        var sec = diff.getSeconds() ;
        var min = diff.getMinutes();
        //var hr = diff.getHours() - 1;

        if (min < 10) {
            min = "0" + min;
        }
        if (sec < 10) {
            sec = "0" + sec;
        }
        if (msec < 10) {
            msec = "00" + msec;
        } else if (msec < 100) {
            msec = "0" + msec;
        }
        if (sec== 0) {
            //clearTimeout(timerID);
            //document.getElementById("cdtime").innerHTML = finishedtext;
            //alert("Your time is Up Switch to Others");
            timerID = setTimeout("cdd()", 100);

            //$("#cdtime").slideUp( 300 ).delay( 8000 ).fadeIn( 400 );  
        } else {
            document.getElementById("cdtime").innerHTML = +sec;
            timerID = setTimeout("cd()", 100);
        } // you can leave out the + ":" + msec if you want...
        // If you do so, you should also change setTimeout to setTimeout("cd()",1000)
    }


    function cdd() {
        now = new Date();
        diff = end - now;
        diff = new Date(diff);
        var msec = diff.getMilliseconds();
        var sec = diff.getSeconds() -29;
        var min = diff.getMinutes();
        //var hr = diff.getHours() - 1;
        if (min < 10) {
            min = "0" + min;
        }
        if (sec < 10) {
            sec = "0" + sec;
        }
        if (msec < 10) {
            msec = "00" + msec;
        } else if (msec < 100) {
            msec = "0" + msec;
        }
        if (sec == 0) {
            clearTimeout(timerID);
            confirm("Time is over");
        } else {
            document.getElementById("cdtime").innerHTML = +sec;
        } 
        timerID = setTimeout("cdd()", 100); 
    }

    window.onload = cd;
</script>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
    <span id="cdtime"></span>
</body>
</html>

嗨我需要在60秒后制作计时器60秒，另外30秒需要在网页上运行。在那里我给出了一个条件，如果（秒== 0）意味着另外30秒想要运行，但问题是什么意味着它显示NaN为0，我给出了条件。所以请帮助我如何在没有NaN的情况下做。所以计时器要先运行60秒，30秒后不要显示NaN（不是数字）。

Answer 1

setTimeout函数的第一个参数是函数或函数的名称（不是调用）。所以你应该替换所有这些行：

timerID = setTimeout("cd()", 100);：timerID = setTimeout(cd, 100);

有关setTimeout功能的详细信息，请参阅here。
出于某种原因，在cdd函数中有以下行：

var sec = diff.getSeconds() - 29;

返回负值并在此行之后：

sec = "0" + sec;

sec的值等于0-*the number*（例如"0-10"），这不是您所说的数字。

可能的解决方案是使用Math.abs()来获得sec变量的绝对值。就像这样：

var sec = Math.abs(diff.getSeconds() - 29);

javascript计时器在给出条件时返回NaN

1 个答案: