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System.NullReferenceException when checking Count of DataTable rows

Why do I get object reference error here if I've clearly defined my 2 data tables?

Dim dtPhones As DataTable = GetInfo(Int32.Parse(syStudentID))
Dim dtPhonestest As DataTable = GetPhoneList(CInt(Request.QueryString("LeadID")))

If ((dtPhones.Rows.Count > 0) AndAlso (dtPhonestest.Rows.Count > 0)) Then

System.NullReferenceException: Object reference not set to an instance of an object.

it's referring to dtPhones.Rows.Count > 0

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TSmooth

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Dustin Hopkins

From what you've given, it looks to me like the problem lays with the count method. You should try changing the "rows.count > 0" to "rows.count -1 > 0"
The reason is count, counts all the rows in the datagrid...including "0". So you must subtract 1 in order for the numbers to match.
So your code would look like this:
Dim dtPhones As DataTable = GetInfo(Int32.Parse(syStudentID))
Dim dtPhonestest As DataTable = GetPhoneList(CInt(Request.QueryString("LeadID")))
If ((dtPhones.Rows.Count - 1 > 0) AndAlso (dtPhonestest.Rows.Count - 1 > 0)) Then

If that doesn't fix it then you should what TSmooth said and debug values.

Dustin Hopkins

I'm sorry I misread what you were doing. what I wrote above was for if you were looping through the table. TSmooth is right, you should output the results of those functions to make sure they're outputing what you think they are.