Error - Operator '=' Is Not Defined For Type 'DBNull' And String "test"
Feb 23, 2010
I have the following query
Dim get_rmf_2 = From rmf In t_rmf _
Where rmf!NIVP = nivp_rap
When i run it i get an error :
Operator '=' is not defined for type 'DBNull' and string "test".
I suspect this is because the column "NIVP" in the datatable contains null values, I've tried yhe same thing without null values and it works.So how can i make this work ? ; the column "NIVP" really has a row "test" , and a normal SQL query works fine.
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim connectionString As String Dim cnn As OleDbConnection Dim adptr As OleDbDataAdapter
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If AllocatedDGV.Rows(i).Cells("RoomNumber").Value = RoomsAvailableDGV.Rows(j).Cells("RoomName").Value Then
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$Con.open() $Dim cd as new oledb.oledbcommand("Select Quantity from tlist where tool_name"& "'"listbox2.selecteditem & "'" & "", con)
[Code]....
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here is my code lblShipping.Text = reader("CARRIERCODE")
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Error Message Operator '&' is not defined for types 'String' and '1-dimensional array of Byte'.
Complete Coding:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim fileSize As Integer Dim rawData() As Byte
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We have a low level class that holds field values for each record read from the files.
This just holds two values, the value read from the file (DBValue) and the updated value that may need to be written back to the file (CurrentValue).
These values may be any of the standard value types (integer, date etc) or a string.
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But we have an office policy of having option strict on all the time.
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Question, how should I change the following code to handle option strict on ...
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Dim ClientsAssetID As Guid = New Guid(ClientsAssetIDTextBox.Text) Dim Client1 As Guid = New Guid(Client1TextBox.Text) Dim Client2 As Guid = New Guid(Client2TextBox.Text)
[code]....
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Imports System.Data.OleDb Public Class Add Private Sub DisplayRow()
Error 1Server Error in '/ Application. -------------------------------------------------------------------------------- Conversion from type 'DBNull' to type 'String' is not valid. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.InvalidCastException: Conversion from type 'DBNull' to type 'String' is not valid. Source Error: Line 64: Line 65:
