InLine IIF Expression & DataBinder.Eval not operating as expected

[Kosababy]

I'm trying to strip characters from the end of a string using \[code\].tostring.remove(n)\[/code\]. with the code below the \[code\]IIf\[/code\] statement confirms the string is ISNullOrEmpty and returns \[code\]True\[/code\] or \[code\]False\[/code\]. If \[code\]true\[/code\] is returned the string of \[code\]""\[/code\] is placed in the aspx page (this works fine), the problem arises in the second part which is triggered when the IsNullOrEmpty returns \[code\]False\[/code\].Upon a \[code\]False\[/code\] value the strings length is checked, if the string is equal to or more than 17 characters long the a \[code\]True\[/code\] value is returned and the string is truncated using the \[code\].ToString.Remove(n)\[/code\] if a \[code\]False\[/code\] value is returned then the string is left untouched.the problem is that if the string is 1 character or 20 characters long the following error keeps occurring:\[code\]startIndex must be less than length of string\[/code\]here is the code block:\[code\]<%# IIf(String.IsNullOrEmpty(Convert.ToString(DataBinder.Eval(Container.DataItem, "SponsorEmail"))),"",IIf(Convert.ToString(DataBinder.Eval(Container.DataItem, "SponsorEmail")).Length > 17,Eval("SponsorEmail").ToString.Remove(17),Eval("SponsorEmail")))%>\[/code\]The database tables the databinder is drawing it's data from does allow NULLS, and it only happens when a NULL or Empty string is present for any given record.Help Please, it's driving me nuts!!!