I am querying a datagridview and it works great unless one of the cells has nothing (dbnull). How to over come this?Exceptions: Operator '=' is not defined for type 'DBNull' and type 'DBNull'.
Dim query = From row As DataGridViewRow In DataGridView1.Rows _
Where row.Cells(SelectedColumnIndex).Value = filter _
And row.Visible = False _
Select row Distinct
I have error. How I can fix this? My error message is "The value for column 'Type' in table 'Fields' is DBNull."
Dim adapterFields As New _MyDatabase_1DataSetTableAdapters.FieldsTableAdapter
Dim fieldsRow As _MyDatabase_1DataSet.FieldsRow
For Each fieldsRow In adapterFields.GetDataByCategory(Me.ComboBoxCategory.SelectedValue)
msgbox(fieldsRow.Type)
Next
I'm getting the error "Conversion from type 'DBNull' to type 'Date' is not valid."here's the line generating the error.
dtReady.Value = dSet.Tables("Db").Rows(Inc).Item("Fixed_Date")
I'm using a date/time picker control and sending the db value to it. I know that the value is null, but I don't understand why the Picker can't be blank. Is there a way to let it be blank? Or should I set up a way to check for nulls and assign today's date or something just in case?
how can I solve this error without having to fill all of my fields. Some of the fields in my database are Nulls and some have records.
Error: Conversion from type 'DBNull' to type 'String' is not valid.
I was tried to get quantity from db make use of the selection in list box. I got answered with listbox1. If i selected the item in listbox1 the quantity would appear in textbox1. But in this same code will not work for listbox2 with textbox4.. Here i given the code...
$Con.open()
$Dim cd as new oledb.oledbcommand("Select Quantity from tlist where tool_name"& "'"listbox2.selecteditem & "'" & "", con)
[Code]....
Here i got the error as "Conversion from type DBNull to type string is not valid"
I've been getting this error when pulling data from a recordset. It is coming from a null entry and as a newbie to VB2008 I'm not sure how to get around this.
here is my code lblShipping.Text = reader("CARRIERCODE")
the error:Conversion from type 'DBNull' to type 'String' is not valid. Basically what i'm attempting to accomplish is to see if there is anything in that field. If so put it into the text box if not leave it blank.
I've got the following LINQ Statement:
[code]...
invRecord.Pack_Num is a field of type Integer. This means that when I try to access it, if it is DBNull I get a StronglyTypedException. The above code throws this exception. If, however, I remove the "invRecord.Pack_Num = PSNum" and in its place put something like "True", the code works fine. So I guess my question is, why is that that invRecord.IsPack_NumNull() returns False when the value is in fact DBNull and what can I use as a conditional instead? I've been beating my head against the wall for a while now and I can't find a solution to this problem.
I've spent the last three day on this. Hope someone can shed some light on the problem.I have a datagridview I which to total a column and place in a textbox. with the coding below I do get the first number and it is place correctly in the textbox but when I complete the data row and move to the next, I receive the following error. "object cannot be cast from DBNull to other type." Read and tried a lot of ideas on line , could not get any of them to work.
[Code]...
Failure is not an option! But sometime you need to look at those option.
In my ASP.Net Web-Application, I'm getting this error: Conversion from type 'DBNull' to type 'Boolean' is not valid.
[Code]...
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.
I'm trying to add a new record to my database but i keep getting the message - "conversion from type DBnull to type string is not valid". I think its something to do with the Employee ID when VB attempts to save it to the database my code is below
Imports System.Data.OleDb
Public Class Add
Private Sub DisplayRow()
[Code]....
I am pulling data from a local MSSQL database using a stored procedure, then send the data to a web service. Every part of the component works well except for a pesky problem will a DBNull being returned from the DataRow field, when I know that the field is not null and has valid data. The database and associated INSERT statements that add to this field are designed to not allow NULL entries. When I debug break the program on or right before the line that throws the error I see that the field has valid data for the current row.If I add a null check to the code (as below) the operation continues as normal:
Dim dataResultsTable = Me.myViewTableAdapter.GetData(int)
For Each myDataRow In dataResultsTable.Rows
If worker.CancellationPending Then
[code]....
Why is the read operation returning DBNull instead of the data in the database?
EDIT: Just to be clear, the operation does return the proper data, but the data is not being saved into the variable.
I have these errors when creating my website?
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:
Could anyone assist me in solving my problem ? My code was written in VB (VS 2003.)I got this error: System.InvalidCastException: Cast from type 'DBNull' to type 'Integer' is not valid. in my code.Here is the code line where I am getting the error: LeadCampusID = CInt(.Item("mkCampusID"))I fixed the error by making the changes in the code as :
If Not IsDBNull(.Item("mkCampusID")) Then
LeadCampusID = CInt(.Item("mkCampusID"))
Else
[code].....
I use following codes to retrieve data from table, but get error Conversion from type 'DBNull' to type 'String' is not valid.
str = "Select * from gpass where vou_no= " & Val(Me.txtGat.Text) & " And Date = '" & Me.txtDat.Text & "'"
dt = GetTable(str)
If (dt.Rows.Count > 0) Then
[code]....
I am importing an Excel spreadsheet, turning it into a dataset and inserting the results into SQL Server (only 100 rows).
I am having an issue with one of the date columns in Excel, which can have a value or not. The "F" column is the one that may be blank and this is the error I get: Conversion from type 'DBNull' to type 'String' is not valid.
How can I add a check to the Dim F As Date = CDate(row(5)) to handle a null?
VB
' The use of letters instead of
' more descriptive variables is
' strictly for this sample peice
[Code].....
When I close my form without saving I want to check if the data on my form has changed since the last time I saved the data.This peace of code, which I included at the bottom always worked fine.Except when I compade a DateTimePicker with a null value in the db.Than I get the error "Conversion from type 'DBNull' to type 'Date' is not valid."Probably on this peace of
Me.dtpVrijeDatum01.Value.Date <> CDate(reader("VrijDatumVeld01")).Date Or
Me.dtpVrijeDatum02.Value.Date <> CDate(reader("VrijDatumVeld02")).Date Or
Me.dtpVrijeDatum03.Value.Date <> CDate(reader("VrijDatumVeld03")).Date Or
Me.dtpVrijeDatum04.Value.Date <> CDate(reader("VrijDatumVeld04")).Date Or
Me.dtpVrijeDatum05.Value.Date <> CDate(reader("VrijDatumVeld05")).Date Or
The total code to check the changes is:
Private Sub CheckForChanges()
LeesCheckboxWaarde(Me.chkFacAdrIsBezAdr, intCheckFacAdresIsBez)
LeesCheckboxWaarde(Me.chkPosAdrIsBezAdr, intCheckPosAdresIsBez)
[code]....
At run time my application gives an error of "Conversion from type "DBNull" to type "String" is not valid. In my form only one field - Add_info is an optional field which might be filled or not by the user. Before, I had an error when an apostrophe was used so i updated the code as highlighted below. This in return removed the apostrophe error but generated an error whenever there is an empty additional field. [code]
View 1 RepliesI am using a code to generate an id for a table.But it is giving 'Conversion from type dbnull to type integer is not valid' exception.Now I know that this is due to the table being an empty set.But it works properly if there is already a row in the table. [code] When I click on 'new' button it generates an id pattern in the textbox 't1'.But it gives that dbnull exception first.I am using mysql as backend and Visual Studio 2008 as frontend.Any ideas?
View 6 RepliesI have a query in my DAL that results 1 item, a date. It's either a date or null. But I get an error when the value is null. Conversion from type 'DBNull' to type 'Date' is not valid. Query
[Code]...
i have code below...but i cannot run because this error..."Conversion from type 'DBNull' to type 'Boolean' is not valid."
CheckBox1.Checked = DataGridView2.CurrentRow.Cells(10).Value
CheckBox2.Checked = DataGridView2.CurrentRow.Cells(11).Value
CheckBox3.Checked = DataGridView2.CurrentRow.Cells(12).Value
CheckBox4.Checked = DataGridView2.CurrentRow.Cells(13).Value
CheckBox5.Checked = DataGridView2.CurrentRow.Cells(14).Value
how i have to set in my table to insert input 1 or 0..
I am getting this exception from the following VB.NET code for only certain months: System. InvalidCastException: Conversion from type 'DBNull' to type 'Date' is not valid.It happens on the line:if CDate(dRow("CompleteDate")).ToString("d") = arrWeekYear(i, 1).ToString("d") Then.If I understand this correctly, then the problem is I am trying to compare some NULL values for CompleteDate to a non-NULL value.However for some of the more recent records, it does not. But I am able to get output from the T-SQL query with same date range and there are no errors; it runs quickly also. And I examined this T-SQL query for both "Date_ Completed" and "Review_Date" NULL values, but either way,"CompleteDate" was always = NON-Null value.So I do not understand how this is happening.[code]When I add this line above the error-causing line above, my report times out for these months.If Not dRow("CompleteDate") Is System.DBNull.Value Then
View 2 RepliesI am getting the above error msg with [code]...
View 10 RepliesIm trying to check a specific item if its already expired. And for some reason, im getting this error "Conversion from type 'DBNull' to type 'String' is not valid."
View 3 RepliesI updated an MS Access file with data and it showed the data is there. When I tried to retrieve I get this message " Conversion from type DBNULL to type Double is not valid" Below is the code to retrieve.
[Code]...
I am pulling records from an access database onto my form and have a "Next" button to get to the next record, but every time it gets to the 5th record, the error msg, "Conversion from type DBNull to type String is not valid." because one of the text boxes (fields) from the database is empty.
View 5 RepliesThe following code at run time gives the error - Opearator '=' is not defined for type DBNull and type 'Boolean'.
The reason is the data at the table is set as NULL value.. How can I change it to accomodate the error.
Dim irowNo As Integer
For irowNo = 0 To DgvReturns.Rows.Count - 1
If DgvReturns.Rows(irowNo).Cells(2).Value = True Or
[Code]......
I'm using the following code to assign record fields to variable:
Dim IPAddress As String = dt.Rows(i)("IPAddress")
Unfortunartely if the field is empty in the row i get the following error:
Conversion from type 'DBNull' to type 'String' is not valid.How can I get around this error?
[code] this code is located on my save button. i get this "Conversion from type 'DBNull' to type 'Integer' is not valid" error on "ID = cmdUser. ExecuteScalar at the 2nd block of codes('addlab') it has a value of 1 which is correct as i wanted to get the ID from supplier and then pass it to the laboratory. what may be the cause of the error?
View 4 RepliesWhy does the following query raise the error below for a row with a NULL value for barrel when I explicitly filter out those rows in the Where clause?
Dim query = From row As dbDataSet.conformalRow In dbDataSet.Tables("conformal") _
Where Not IsDBNull(row.Cal) AndAlso tiCal_drop.Text = row.Cal _
AndAlso Not IsDBNull(row.Tran) AndAlso tiTrans_drop.Text = row.Tran _
[code]....
Run-time exception thrown : System.Data.StrongTypingException - The value for column 'barrel' in table 'conformal' is DBNull.
How should my query / condition be rewritten to work as I intended?