Thank you sri. This helped me.

Thanks Brian.

I took a look at your sample and I've found the solution: the constructor of the form is too early to assign the sort comparer. I added it to the Load handler for the form which occurs after construction, and now it seems to work fine.

Thanks!

I tried this in a simple sample and it seems to work for me (using latest 2009.2 source). I attached the project for your reference.

Thanks for the response.

When I use breakpoints on the comparer I see that the sort happens as soon as it is assigned to the column (rather than when the header is clicked, which is what I expected would happen). The grid column is of type string. The idea is that values that are numeric are sorted numerically, and the rest are sorted alphabetically.

As far as I can tell the comparer seems to be working ok -     1 compared to 28000 returns -1 (1 < 28000), 28000 compared to 8921 returns 1 ( 28000 > 8921)

I've tested this against an arraylist of strings and it sorts as expected.

class InvoiceNumberSort : IComparer
	{
		public int Compare(object o1, object o2)
		{
			UltraGridCell cell1 = (UltraGridCell)o1;
			UltraGridCell cell2 = (UltraGridCell)o2;
 
			string strValue1 = UltraGridCellExtensions.ValueOrDefault(cell1, string.Empty);
			string strValue2 = UltraGridCellExtensions.ValueOrDefault(cell2, string.Empty);
			
			int nValue1 = 0;
			int nValue2 = 0;
 
			bool value1IsInt = int.TryParse(strValue1, out nValue1);
			bool value2IsInt = int.TryParse(strValue2, out nValue2);
 
			int comparison = 0;
 
			if (value1IsInt && value2IsInt)
			{
				if (nValue1 > nValue2)
				{
					comparison = 1;
				}else if (nValue1 < nValue2)
				{
					comparison = -1;
				}
				else
				{
					comparison = 0;
				}
 
			}
			else
			{
				comparison = (new CaseInsensitiveComparer()).Compare(strValue1, strValue2);
			}
			
			return (comparison);
		}
	}