How To Check If A Datatable Is Null Or Nothing .net
Apr 26, 2012How can I check if a datatable has never been set ? or Null or Nothing ? I don't mean empty Datatable ... For example,
[Code]...
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Syntax Error Null Check Datatable / Gridview Asp.net Vb?
May 21, 2010I have this code:Dim Result As New DataTable DataAdapter.Fill(Result)
'bind data to visible surname/name grid If Result.Rows.Count = 0 Then NoInputBottom.Text = "No Results. Please widen your search criteria and try again" NoInputTop.Text = "No Results. widen your search criteria and try again" Else
GV.DataSource = Result
GV.DataBind()
End If
I have also tried moving the check to the gridview like so:
If GV.Columns.Count = 0 Then
NoInputBottom.Text = "No Options Selected: Please select your search criteria and try again"
NoInputTop.Text = "No Options Selected: Please select your search criteria and try again"
End If
When I run the code. the noinput labels do not have value, the null check seems to be failing? Please can you tell me how to display a message if the search returned no reults.
Linq To Sql Null - Check Whether A Column Is Null
Jul 15, 2011How to check whether a column is null i use the following code but I got this error "Input string was not in a correct format."
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Have A Field In A Datatable (dt) That Can Be Integer Or NULL?
Mar 1, 2010I have a field in a datatable (dt) that can be integer or NULL.
View 7 RepliesNull Exception Error When Loading Datatable?
May 20, 2010I am loading data from an excel sheet using the following code.The first test I did worked fine.But when I tried another sheet it errored on a cell that was blank"Object reference not set to an instance of an object".Even though the sheet in the first test had blank cells.I need the loop to load the blank cell in the datatable
For nRow = 1 To objSheet.UsedRange.Rows.Count - 1
dr = dt.NewRow
For nCol = 0 To objSheet.UsedRange.Columns.Count - 1
[code]...
Add A Null Column To A Row In A Typed Datatable's Addrow Method?
Jul 14, 2010vb.net 2005
Here is one attempt:
Dim myRow As BurnerService.OEBSContractBatchesRow
Dim myDate As Nullable(Of DateTime)
myRow = Me.BurnerService.OEBSContractBatches.AddOEBSContractBatchesRow( _
[Code].....
VS 2005 Storing Null Values In Access From Datatable?
May 22, 2009Did anyone knows where can I upload a folder so my programe to be able to download an update from there???
View 3 RepliesNull Check Always Returns Null, If Removed Returns Object Reference Not Set To An Instance Of An Object
Jun 24, 2010I have some code which gets child items for a menu via the GetChildren function which takes a list of menuData: Dim builtMenu As New List(Of MenuData)(_rawData.FindAll(Function(item) item.GroupingID = 0))
For Each menuData As MenuData In builtMenu
If menuData.Children IsNot Nothing Then
menuData.Children.AddRange(GetChildren(menuData))
End If
Next
If I check if menudata.children isnot nothing, it always is nothing because the GetChildren function is yet to run (providing the child items, which do exist). If I remove this check and just have this code:
Dim builtMenu As New List(Of MenuData)(_rawData.FindAll(Function(item) item.GroupingID = 0))
For Each menuData As MenuData In builtMenu
menuData.Children.AddRange(GetChildren(menuData))
Next
Then I am presented with a Object reference not set to an instance of an object error on menuData.Children.AddRange(GetChildren(menuData))
C# - Sorting DataTable String Column But With Null / Empty At The Bottom
Feb 7, 2011I need to sort a DataTable or DataGridView by a column that is a string value, but with null/empty values at the BOTTOM when sorting ASCENDING. The DataTable is NOT populated by a SQL statement, so no order by. If I do
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Inserting Null Value In A DataTable Of MS Access2003 Through Application Created In VB 2010?
Jun 8, 2011I am facing a problem in inserting a datarow in the Ms access Database though visual basic application.The scenario is like this:I have a table named 'IssueReturn' for library management System. The table has these fields:
MemId Char(10)
BookId Char(10)
DateOfIssue DateTime
[code]....
Sorting DataTable String Column, But With Null/empty At The Bottom?
Mar 5, 2009I need to sort a DataTable or DataGridView by a column that is a string value, but with null/empty values at the BOTTOM when sorting ASCENDING.The DataTable is NOT populated by a SQL statement, so no order by.If I doDataGridView1.Sort(New RowComparer(System.ComponentModel.ListSortDirection.Ascending))then it throws an exception, saying that the DataGridView is DataBound, which is correct, but doesn't help me, and I want to keep it databound.
View 2 Replies.net - Null Check In VB?
Apr 7, 2011All I want to do is check if an object is null, but no matter what I do, if it compiles, it throws a NullReferenceException just trying to check! Here's what I've done:
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Check For NULL And For Zero?
Apr 8, 2011I have a dataset. I'd like to check if one item in the dataset is null or zero.
If IsDBNull(ds.Tables(0).Rows(0)("TotalCostPerUnit")) or CInt(ds.Tables(0).Rows(0)("TotalCostPerUnit") = 0 Then
Exit Sub
end if
Check For Null Value?
Sep 30, 2009Dim Conn As ADODB.Connection
Dim Null As String
Dim NullRecordset As ADODB.Recordset
[code]....
Im trying to check my database for a null value. If the database is null, then I want it to start the timer, otherwise I want it to skip over some stuff and automatically load the main form.
Check If DB Null?
Oct 27, 2011I am trying to check to see if a DataSet is null or not. If it is I would like to show a MessageBox. For some reason it is not recognizing null returns and skipping the message box and going right to the Else commands. [code]....
View 3 RepliesHow To Check DB Null Value
Aug 13, 2010I have a problem with verifying db null value. Actually I don't know the syntax.
Here is the code.
If Not IsDBNull(Me.DeliveryReviewDataSet.Delivery(Me.CustomerIDListBox.SelectedIndex).Signature) Then
"Signature" is the image field (binary data).
How To Check For Null Value
Jun 29, 2010Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If MyBase.Dispose(disposing) <> DBNull.Value Then
Dispose() = DBNull.Value
[Code]....
I am getting error
1) Expression does not produce a value.
2)Expression is a value and therefore cannot be the target of an assignment.
Sql - How To Check If It's Null
Sep 21, 2009I retrieve data from database like below. How do I check whether the value retrieved from database is null?
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Check Column Value For Null Vb?
Mar 11, 2012i'm working with a database application and i want to check if there is a null value in a specific column but it works only when its not null but if its null it throws an exception automatically
i tried to change the nullvalue property of this column but i'm not able it shows a message that its not a valid property
i tried to change the source code in the code editer but it changes back automatically
Check For Null Integers?
Jul 8, 2010I am working on a program that has many integers (q1, q2, etc.), and each of them can be 0 or 1. This is dependent on which radiobuttons are selected. I need it to check and make sure that all of the integers have a value, but since "Null" is the same as "0",
View 8 RepliesCheck If Value Is Null Before Running
Mar 2, 2011I have multiple textboxes that are saved using my settings and buttons to add them to the clipboard.
The problem is when the textbox is blank and I click on the copy button.
The saving to my.settings happens on close so when someone enters text that they plan on saving later and then clicks the copy button, whammo it crashes.
Here is the code that is failing and I need to check to make sure that there is a value before setting the text on the windows clipboard.[code]...
Check To See If Object Is Null
Jun 29, 2009I just want to check and see if this object is null. if i do not and it is my applications closes.I have also looked into a null reference exception. I will do whatever as long as it handles "null".[code]
View 2 RepliesHow To Check If A Textbox Has A Null Value
Nov 28, 2007[if me.textbox1.text= system.dbnull then msgbox("please inter a value")] it says system.dbnull can't be used as an expression so how can i check the if the textbox has a null value
View 13 RepliesVS 2005 How To Check If Its NULL
Jan 24, 2010Table contains 2 columns Tags10 and TU. Its values are:
NDX___________TUI48
JJI_________ NULL
CmdSelect.CommandText = "Select * From Tags Where Tags10='" & s_temp02 & "'" 'OK
ReaderSelect= CmdSelect.ExecuteReader() 'OK
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How to check this? If NULL there is nothing to do, if not NULL, we should put the value into s_temp03.
.net - Check If Datagridview Cell Is Null?
Feb 9, 2011I want to display a message if the value of cell of my datagridview is Null.
View 1 RepliesCheck A Datagridview Cell For A Null Value?
Oct 13, 2009What im trying to do is check a row for null values in my datagridview before saving the data back to my access database, in particular the first columns cell of the new row being added. This is the code I have so far'
Private Sub LatheprogramsBindingNavigatorSaveItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles LatheprogramsBindingNavigatorSaveItem.Click
Dim test As String = Me.LatheprogramsDataGridView.Columns(1).ToString()
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Check If Function Returns A Null Value?
Apr 2, 2011i hav two openfilefialogs(1 and 2). So i also have a listbox. the files opened with the openfiledialogs will be added to the listbox. and when i need to open the files i need to see if they are from which openfiledialog. so
it is like this.
Path.GetDirectoryName(OpenFileDialog1.FileName) & "" & Form3.ListBox1.SelectedItem.ToString
'if this returns a null then go to this
Path.GetDirectoryName(OpenFileDialog2.FileName) & "" & Form3.ListBox1.SelectedItem.ToString
Check Multiple Expressions For Null?
Oct 14, 2011Check multiple expressions for null?I have this bit here[code]...
View 8 RepliesCheck Null And Empty Both At A Time?
Jun 17, 2009 I am getting product id value some times null and empty from databasehere how i check if valule null and empty
productid = IIf(IsDBNull(TempDT.Rows(0).Item("productid")) =
True,
"", TempDT.Rows(0).Item("productid"))
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DataGridView - How To Check Item If Null Or Not
Sep 17, 2008DataGridViewX.CurrentRow.Cells.Item(0).Value.ToString
If the item is blank and no data is entered it will throw a null exception, so the question is that how can I check if the item is null or not? Even using this:
If DataGridViewX.CurrentRow.Cells.Item(0).Value.ToString IsNot Nothing Then ...
Will throw the exception!