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POWrong result when checking if datetimes in JavaScript are equal
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  1. POWrong result when checking if datetimes in JavaScript are equal
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    copied!<p>In my JavaScript code I have to variables (x and y) with datetime values. All of the following statements return false:</p> <ul> <li>x &lt; y -> false</li> <li>x > y -> false</li> <li>x == y -> false</li> <li>x === y -> false</li> </ul> <p>When I debug the code both x and y have the same value 'Sat Jan 1 12:00:00 UTC+0100 2011' and the same type.</p> <p>I am using IE9.</p> <p>Is there a different way to check if two datetime values are equal?</p> <p><strong>update (code)</strong> - I tried to extract some relevant parts, whole project is very big:</p> <pre><code>var data; //Dates are loaded from a webservice and returned as strings; they are parsed with the following function data = parseD(getDataFromService()); function parseD (data) { for (var i = 0; i &lt; data.length; i++) { var d = data[i]; for (var key in d) { if (d[key] &amp;&amp; d[key].toString().substring(0, 6) === "/Date\(") d[key] = new Date(parseInt(d[key].toString().substr(6))); } } return data; }; function getCssForCell(row, columnID, dataContext, value) { var css = ""; if (columnID === "VF" &amp;&amp; value) { if (row &gt; 0) { if (data[row].VF &lt; addDays(data[row - 1].VF, 2)) { css = "error_cell"; } } } if (columnID === "VU" || columnID === "VF") { if (dataContext.VF &amp;&amp; dataContext.VU) { if (dataContext.VU &lt;= dataContext.VF) { css = "error_cell"; } } } if (columnID === "Rate" &amp;&amp; row &lt; (strict_mode ? data.length - 1 : data.length - 2)) { //value for Rate must be assigned if (value === undefined || value === null) { css = "error_cell"; } } if (columnID === "VF" &amp;&amp; row &lt; (strict_mode ? data.length - 1 : data.length - 2)) { if (value === undefined || value === null) { css = "error_cell"; } } if (columnID === "Rate" &amp;&amp; value &lt; 0) { css = "error_cell"; } //PROBLEM IN NEXT LINE if (columnID === "VU" &amp;&amp; row &lt; data.length - 1 &amp;&amp; dataContext.VU &amp;&amp; data[row + 1] &amp;&amp; addDays(dataContext.VU, 1) != data[row + 1].VF ) { css = "error_cell"; } return css; } function addDays(date, days) { if (date) { var result = new Date(date.getFullYear(), date.getMonth(), date.getDate(), date.getHours()); result.setDate(result.getDate() + days); return result; } return date; } </code></pre>
 

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