asked on

Function to Return DataSet

I want to write a function to return the results of a SQL query as a dataset. I'm calling it like this:

Dim dsResults As Data.DataSet = New Data.DataSet
dsResults = databaseFunctions.ExecuteQuery("SELECT * FROM tUsers")

But I keep getting this error on the second line:
System.NullReferenceException: Object reference not set to an instance of an object.

Function ExecuteQuery(ByVal txtQuery As String) As Data.DataSet
OpenDB()
cmd = New SqlClient.SqlCommand
adItem = New SqlClient.SqlDataAdapter
dsResults = New Data.DataSet
cmd = New SqlClient.SqlCommand(txtQuery, cn)
adItem.SelectCommand = cmd
adItem.Fill(dsResults)
ExecuteQuery = dsResults
CloseDB()
End Function

ASKER CERTIFIED SOLUTION

Torrwin

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rodmjay

is option explicit turned off?

CodeManiac

ASKER

Thanks Torrwin!

Can you give an example of how you call your function?

Do you declare a dataSet variable like I tried above?

SOLUTION

Havagan

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Torrwin

Paul is right, that's how I essentialy do it:

Dim ds as New Dataset
Dim sSQL as String
sSQL = "SELECT * FROM AUTHORS"
ds = SelectCommand(sSQL)

CodeManiac

ASKER

I'm getting an "Object reference not set to an instance of an object." error when I call the function like this...

Dim ds As Data.DataSet = New Data.DataSet
ds = databaseFunctions.SelectCommand("SELECT * FROM tUsers")
With ds.Tables(0)
For i = 0 To .Rows.Count - 1
Response.Write("test" & i)
Next
End With

Any ideas?

Post your answer at the following URL to get another 500 points...
https://www.experts-exchange.com/questions/21393393/Object-reference-not-set-to-an-instance-of-an-object.html

Thanks!