argh!
Can\'t stand it that i can\'t figure it out myself....
i\'ve used this in the formatting of a number in my report:
\'€\' #,0.00;(\'€\' #,0.
You can find the definition of the comma and period dynamic behavior here: http://msdn.microsoft.com/en-us/library/0c899ak8.aspx
I think the best way to reliably get what you want is to hard code a locale into the expression for this field.
= (new Decimal(11123.55)).ToString("€#,0.00;(€#,0.00)",
new System.Globalization.CultureInfo("es-ES"))
This will always use the comma as decimal, and period as millions, thousands &c.
There are ways to be more dynamic and always return in the clients local set format, that would usually be preferable.