SSRS Expression Cheat Sheet

Problems	Expression
Return first day of current Week  (ex. Default Start Date parameter to return WTD)	Expression on the parameter default value:  =DateAdd("d",-DatePart(DateInterval.WeekDay,Today,0,0)+1,Today)  Expression Output Example: 11/7/2010 12:00:00 AM
Return first day of current Month  (ex. Default Start Date parameter to return MTD)	Expression on the parameter default value: =DateAdd("d",-(Day(today)-1), Today) or =DateSerial( year(today()), month(today()), 1)  Expression Output Example:11/1/2010 12:00:00 AM
Return first day of current year  ex. Default Start Date parameter to return YTD)	Expression on the parameter default value:  =DateAdd("d",-DatePart(DateInterval.DayOfYear,Today,0,0)+1,Today)  Expression Output Example: 1/1/2010 12:00:00 AM
Return period over period  (ex. Default date parameters to a rolling year)	Expression on the parameter default value:  Week over Week  =DateAdd("ww",-1, Today)  Month over Month  =DateAdd("m",-1,Today)  Year over Year  =DateAdd("yyyy",-1, Today)  Expression Output Example:10/9/2010 12:00:00 AM
Return current month name	Expression in Text Box:  =MonthName(Month(Today()))  Expression Output Example:November
Uppercase fields	Expression in Text Box:  =UCASE(Fields!FieldName.Value)  Expression Output Example:NOVEMBER
Convert text to proper case  (ex. 1st letter in each word is uppercase)	Expression in Text Box:  =StrConv(Fields!FieldName.Value, VbStrConv.ProperCase)
Replace NULL with another value	Expression in Text Box:  =iif(Fields!FieldName.Value = nothing, "No Value",Fields! FieldName.Value)
Alternating row color (Banding effect)	BackgroundColor property on Text Box:  =iif(RowNumber(Nothing) Mod 2 = 0, "Silver", "White")
Handling division by zero	Expression in Text Box:  =iif(Fields!DenominatorField.Value = 0, 0, Fields!NumeratorField.Value/  iif(Fields!DenominatorField.Value = 0, 1, Fields! DenominatorField.Value))
security number)	Expression in Text Box:  =Replace(Fields!EmailAddress.Value,"-","")

source : http://pragmaticworks.com/Training/Resources/Cheat-Sheets/SSRS-Expression-Cheat-Sheet