Web Forms :: Conversion From Type DBNull To Type String Is Not Valid
Nov 18, 2012
I have a web in ASP.NET AND CODE IN VB MY DATABASE IS ACCESS WHICH WAS CREATED INITIALLY AND OLD DATA IS ACCESSED FROM THIS ACCESS DATABASE.
THE PROBLEM IS WHEN THE FIELD IS BLANK THE FOLLOWING ERROR COMES
Conversion from type 'DBNull' to type 'String' is not valid.
MY CODE IS AS UNDER
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSubmit.Click
Dim PNO As String = inputtxt.Text
Dim connectString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
"Data Source=C:awingAWing.mdb"
Dim con As OleDbConnection = New OleDbConnection(connectString)
con.Open()
Dim qstr As String
qstr = "select * from PersData where PNO='" + inputtxt.Text + "'"
[Code] .....
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