Custom format providers

I need to format data, specifically double numbers, with a custom format.

In my case, if the output is requested to be 7 digits, 3 decimals, a value of:

12.3

should be formatted as:

0012300

It is like fixed point, but with no decimal separator char.

I planned to use a custom format provider, but internally the OnFormat methods use ToString, which not support custom format providers (or better, ignore them when dealing with standard type such numbers).

If String.Format was used, instead, it should work.

I am open to any suggestion which helps me to get the desired result

[jehugaleahsa]

I am pushing out a 4.4.0 release. I am going to eventually retire the IColumnDefinition.Preprocessor property. I have created 4 new lambda properties called OnParsing, OnParsed, OnFormatting and OnFormatted that get called before and after parsing and formatting values.

I am also adding support for setting an IFormatProvider on the options object to override the culture settings globally rather than needing to do it on each column individually.

You’ll have to let me know whether the new delegate properties give you the flexibility you need.

[andrea-rinaldi-microarea]

It worked for me:

.AddColumn(new DoubleColumn("NetWeight") { 
     OutputFormat = "0000.000", 
     OnFormatted = (IColumnContext context, string value) => { return value.Remove(4, 1); } 
}, 7)

values.Add(12.3); // yelds 0012300

I believe I can easily do the reverse job while importing.

Great, many thanks!