javascript比较两个日期并发出警报 [英] javascript compare two dates and throw an alert
问题描述
警报。
我尝试了下面的代码,但它不起作用。
startdate = 14/12/2014 19:00:00;
enddate =21/01/2015 19:00:00;
if(new Date(startdate)> new Date(enddate))
{
alert(结束日期不能小于开始日期);
}
使用以下构造函数创建一个日期:
new Date();
new Date(value);
new Date(dateString);
new Date(year,month [,date [,hour [,minutes [,seconds [,milliseconds]]]]]);
您已经使用了其中的第三个,其中 dateString
是一个
表示日期的字符串值。字符串的格式应为DateParse()方法识别的格式
(符合IETF标准的RFC 2822
时间戳,也是ISO8601的版本)。
您提供的字符串格式不正确。因此,相应的日期对象尚未创建。
我宁愿使用最后一个构造函数,因为我不必相应地格式化字符串格式。
var startDate = new Date(2014,12,14,19,0,0);
var endDate = new Date(2015,1,21,19,0,0);
我将 startDate
与 endDate
,以便我们看到警报。
var endDate = new Date ,14,19,0,0); var startDate = new Date(2015,1,21,19,0,0); if(startDate> endDate){alert(结束日期不能小于开始日期) ;}
I have two dates in DD/MM/YYYY HH:MM:SS format ,i want to compare two dates and throw an
alert .
I tried the below code,but it is not working.
startdate = "14/12/2014 19:00:00";
enddate = "21/01/2015 19:00:00";
if(new Date(startdate) > new Date(enddate))
{
alert("End date cannot be less than start date");
}
You can create a Date using the following constructors:
new Date();
new Date(value);
new Date(dateString);
new Date(year, month[, date[, hour[, minutes[, seconds[, milliseconds]]]]]);
You have used the third of them, where the dateString
is a
String value representing a date. The string should be in a format recognized by the Date.parse() method (IETF-compliant RFC 2822 timestamps and also a version of ISO8601).
The string you have provided hasn't the correct format. Hence the corresponding date objects haven't been created.
I would prefer using the last constructor, since I wouldn't have to format correspondingly the strings.
var startDate = new Date(2014,12,14,19,0,0);
var endDate = new Date(2015,1,21,19,0,0);
I swapped the startDate
with the endDate
, in order we see the alert.
var endDate = new Date(2014,12,14,19,0,0);
var startDate = new Date(2015,1,21,19,0,0);
if(startDate > endDate)
{
alert("End date cannot be less than start date");
}
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