javascript - Conditional Alert in HTML Table -

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• how number of days between 2 dates in javascript? 31 answers

i have managed automatically build html table based on output erp system, , managed use css format easily. last step conditional formatting in date field. if date < make field red if it's between 4 <> 7 days make yellow else "no formatting.

i have gotten far on dozens of examples site, , hoping can me basic date math reason can't head around.

right date field in td:nth-child(4) , want compaire current date.

    <script>      $(document).ready(function() {              $('table td:nth-child(4)').each(function() {                 var d1 = $(this).text();                 var d2 = new date();                  if ((d1 - d2) < 4) {                     $(this).css('backgroundcolor', 'red');                  }                 else if((d1 - d2) < 7) && ((d1 - d2) > 4) {                     $(this).css('backgroundcolor', 'yellow');                  }                 else {                     $(this).css('backgroundcolor', '#99faa0');                  }              });             event.preventdefault();     });      </script> 

you need convert , compare dates properly. below example compare dates.

reference:

get difference between 2 dates in javascript?

var _ms_per_day = 1000 * 60 * 60 * 24;  // , b javascript date objects function datediffindays(a, b) {   // discard time , time-zone information.   var utc1 = date.utc(a.getfullyear(), a.getmonth(), a.getdate());   var utc2 = date.utc(b.getfullyear(), b.getmonth(), b.getdate());   return math.floor((utc2 - utc1) / _ms_per_day); } 

working sample

https://jsfiddle.net/zslfh3kj/1/