Converting DateTime C# to DateTime.UTC javascript

Here is a simple way to change a C# datetime to a javascript Datetime.UTC value that can be used in the highcharts pointstart field.

In C#

 private double DateUTCDate(DateTime date)  
 {  
   return date.Subtract(new DateTime(1970, 1, 1)).TotalMilliseconds  
 }  

This will return a value that can be used directly in javascript

  series: {  
             pointStart: dataFromCsharp,  
             pointInterval: 3600 * 1000 // one day  
           }  

highcharts pointstart only used Date.UTC values if you are timestamp for the x-axis