Hi,
It is very easy to format your decimal values in the grid to for instance 4 decimals using the format string "N4"."Unfortunately" this way to format always use "away from zero" rounding (that's the way the .NET formatting works).I would like to change this to "to even" rounding instead.
First I tried to write my own IFormatProvider and set the column property FormatInfo to my formatting class.This doesn't seem to be possible however (after some investigations in .NET Reflector). The way the UltraGridformats strings ((decimal)dataValue).ToString(this.format, this.formatInfo), the .NET framework only acceptsNumberFormatInfo (which I can't inherit from) or uninherited CultureInfo as formatProvider.(If the UltraGrid had used String.Format(this.formatInfo, this.format, (decimal)dataValue) I guess it hadworked to use your own IFormatProvider.)I hope I'm wrong cause this would be a nice way to solve it.
My second approach was to create a DataFilter to affect the way the decimal value is displayed. I'm addingmy conversion logic in the convert "ConversionDirection.EditorToDisplay"-direction.This works, BUT when I put the cell in edit mode it still shows my formatted value. I want it to behave likewhen setting the format property, i.e. the "real" value is displayed when I go into edit mode.How do I achieve this?
Best Regards-tomas.
"to even": means that 1.22225 is rounded to 1.2222"away from zero": means that 1.22225 is rounded to 1.2223
Hi tomas,
I'm not sure what you mean about a NumberFormatInfo. I don't see that anywhere.
I was able to get this to work like so:
public class MyFormatProvider : IFormatProvider { #region IFormatProvider Members public object GetFormat(Type formatType) { if (formatType == typeof(ICustomFormatter)) return new MyCustomFormatter(); throw new NotSupportedException(); } #endregion } public class MyCustomFormatter : ICustomFormatter { #region ICustomFormatter Members public string Format(string format, object arg, IFormatProvider formatProvider) { decimal argDecimal = (decimal)arg; return (Math.Round(argDecimal, 2, MidpointRounding.ToEven)).ToString(); } #endregion }
SORRY, of course I should have said that I'm using version 2005Vol3. There it doesn't work,but it can be used in 2008Vol1 (didn't try that before, since we are still using the old oneand it was in that version I was looking for a solution).
Regards
-tomas.
Well, v5.3 isn't supported any more - I don't have those assemblies on my machine, so I can't test it. But there must be a way to provide custom formatting, otherwise there would be no point in having a FormatInfo property on the column. What's different in v5.3?
Another option you might consider is hiding the actual bound column and then using an unbound column to display to the user. You could use the InitializeRow event to take the value from the "real" column, format it, and write it into the unbound column.