VS 2010 DataGridView Selected Row Null?
Feb 16, 2011
I am trying to pull data from a cell in the currently selected row in a DataGridView control. I fill the control with data from a SQL database through a dataset.I am trying to retrieve the index of the currently selected row so that I can pull the data out of the first cell in that row. Here is the code I currently have:
Dim i As Integer i = dgvSchedule.CurrentRow.Index MsgBox(dgvSchedule.Item(0, i).Value)Seems pretty simple to me, but for some reason I am receiving a "NullReferenceException, Object reference not set to an instance of an object" error on the second line.
View 9 Replies
ADVERTISEMENT
Jun 9, 2010
I have a databound DataGridView, and I'd like to keep one column in front, with a slightly smaller width than the default. The grid's AutoSizeColumnsMode property is set to Fill so that the columns fill out the entire grid. This makes the first column equally large as all others, which is why I need to set its width manually. The smaller column is the first one with the checkboxes. I have two grids that I need to do this with, and for some reason it works just fine with the first grid, but gives a null reference error on the second grid...
Here's the code for the first grid (working fine):
vb.net
Public Sub UpdateTodoGrid()
' Load todo items
todoGrid.DataSource = _TodoManager.LoadAll()
' Set backcolor
For Each row As DataGridViewRow In todoGrid.Rows
[Code] .....
As you can see, the code is exactly the same (except for not setting the BackColor of each row and not using the ReadOnly property*). When I run this code, it gives me a null reference error ("Object reference not set to an instance of an object.") on the line where I set the column's Width. Obviously 'col' is not Nothing (otherwise it would have errored before that line), and there's nothing else there that could be Nothing... I assume that something happens internally in the grid when you set the width of a column, and that there is a null reference there, but obviously I have no control over that.
The grid's are absolutely the same, as the second grid is just a 'copy' (meaning I copy/pasted it in the designer) of the first. So all their properties are equal. I thought maybe the ReadOnly properties were the problem, but I tried putting them in in the same way and the issue did not go away... The first grid is not ReadOnly (because the checkboxes need to be editable), but all rows except the first are, while the second grid is completely ReadOnly.
View 2 Replies
Dec 29, 2011
in visual basic 2010 How to delete a selected row from datagridview and table then skip to next or previous record
View 1 Replies
Oct 7, 2011
I want to get the value of the selected item for example I want to get the first cell which is the quantity and store it in a textbox which I will select in the datagrid. How can I do that I am new with datagrid.
View 19 Replies
Sep 7, 2010
Im currently creating a point of sales system, I'm having problems in passing selected row in datagridview to another datagridview & text box but in different form.
POS Form
- Selected Row in Product Browse Form must be passed in this DataGridView.
- Selcted Row in Customer Browse Form must be passed in CustomerName and Customer Address Textbox.
[code]....
View 3 Replies
Oct 1, 2011
I have a datagridview on my desktop application, what I need is to show in a a textbox the sum of collums values, of rows selected manually. Is this possible?
View 4 Replies
Apr 16, 2010
I am unable to load the dat into the data Grid. Here is where I keep getting stuck.
dgvOleDb1 = table.Select
dgvOleDb1.DataSource = DataGridViewEditMode.EditProgrammatically
dgvOleDb1.DataSource = ds.Tables(0)
I am confused; I am using VB2010, IBM.iSeries.DB2 on an as400 V5R4. I am trying to establish an OLEDB connection, and return the values from the selected table to a DataGridView. I had one of the admin's make me file named GARBAGE, in the Rprtaccess catalog. In the past, I have been able to connect via access and an ODBC connection. My project is too big for access, and the SQL middleware we have is clunky and not user friendly. This is a program that will generate the SQL statements, specifically the WHERE: clause and populate the datagrid with the selected criteria. In essence I am making a user friendly striped down program, that has variables that are manipulated by the end user, and the rest, referenced tables and libraries are coded.
Imports System.Data.OleDb
Imports System.Exception
Public Class Form11
[code]....
View 1 Replies
Apr 12, 2012
I got this in another post <asp:RadioButtonList runat=server ID="rd" SelectedValue='<%# Bind("sex").GetType() == typeof(DBNull) ? null : Bind("sex") %>'
<asp:ListItem Text="male" Value="1"></asp:ListItem>
<asp:ListItem Text="female" Value="2"></asp:ListItem>
</asp:RadioButtonList>
Is this a correct syntax?? If yes can someone please give the VB version of it??
SelectedValue='<%# Bind("sex").GetType() == typeof(DBNull) ? null : Bind("sex") %>'
View 1 Replies
Dec 9, 2011
I have a property called ReplacementTo and I set a value to it based on the selecteditem from the combobox, like this:
classEquipmentItem.ReplacementTo = cmbReplcmnt.SelectedItem.ToString
Now I can't use cmbReplcmnt.Text because what I actually need is the value of that SelectedItem
So problem is, if the user leaves the combobox as blank, it throws a null exception.I decided to use the IIf function then:classEquipmentItem.ReplacementTo = IIf(IsNothing(cmbReplcmnt.SelectedItem.ToString), classEquipmentItem.ReplacementTo = "", cmbReplcmnt.SelectedItem.ToString)
Unfortunately I still get the error I tried using a Try-Catch for it and it worked, but I don't want to rely on the Try-Catch, so I was wondering is there a another way to work this through?
View 2 Replies
Mar 23, 2012
I have several date fields in a datagridview, in sql these are saved as navchar fields. If the user needs to clear the date they can do so by highlighting the field and pressing the delete key. This clears the date no problem, unfortunately it sets the field to Nothing or "" (a blank). I need it to set it back to NULL for reporting purposes.
Here is the relevant part of the code:
Private Sub dgvWeldingLog_CellEndEdit(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles dgvWeldingLog.CellEndEdit
Try
If dgvWeldingLog.Columns(e.ColumnIndex).Name = "dgvtxtDateWelded" Or _
dgvWeldingLog.Columns(e.ColumnIndex).Name = "dgvtxtFitCheck" Or _
[Code] .....
If there is an error in the data entry then the form cannot be saved. When I trap DBNull.Value is says it is equals to "Nothing" and not "NULL".
View 4 Replies
Feb 9, 2011
I want to display a message if the value of cell of my datagridview is Null.
View 1 Replies
Oct 13, 2009
What 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()
[code]....
View 4 Replies
Sep 17, 2008
DataGridViewX.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!
View 6 Replies
Oct 5, 2011
I have a DataGridView connected to a DataSet. I want to allow the user to update and insert new records on the RowLeave and CellLeave events. The Update method works:
Me.ExpensesTableAdapter.Update(Me.DataSet1.Expenses)
View 2 Replies
May 30, 2009
I have a program in which I am doing a sql select on two tables with an outer join. In one option of my search I need to show all items in both tables so some items in the row will come back with a null value. I am familiar with using the DefaultCellStyle.NullValue = which works great when replacing Null values with the same value.
I am in need of replacing the null value in column 0 with the value in column 10. I think I am close but have not had any luck researching this on my own. Here is what I have.
dgvInventory.Columns(0).DefaultCellStyle.NullValue = CStr(dgvInventory.Item(10, ???).Value) if I replace the ??? with any value I get that rows data but all null values become the same, what can I do to tell it to replace the current rows column 0 with the current rows column 10 if column 0 is null.
View 3 Replies
Jan 16, 2010
I want to have my current row stand out as the current row by virtue of the background color.I also want my current cell stand out from the row color.
in other words i want to controll the background of the current cell as well as the current row, and have these colors different from each other as wel as the background from the non current cells.
I am getting confused with the notion of the current row vs the selected row.I have tried messing with the default row style.selectedbackgroungcolor as well as the same for the default cell style, but cant get it to work the way i want.
i can almost get it if i set the selection mode to full row, but then cannot get the current cell to have a different background color.
View 6 Replies
Nov 15, 2009
I key-in data from textbox to datagridvie..........the date data the format datatable is:
[Code]...
View 1 Replies
Jul 28, 2010
I have a datagridview that has three columns. All three fields are unique fields in the Access table that the datagridview reads from in order to make sure that an entire record is unique. I have a form where a user can add a new record. Upon opening the form, two of the three fields have data automatically entered, leaving one field for the user to enter information. The field that the user needs to enter information in is put in edit mode. The problem I am having is that I have a Cancel button if the user does not want to enter a new record and wants to close the form. I tried using the following line of code to remove the current record that has information in two of the three fields before closing the form:
PriceHistoryBindingSource.RemoveCurrent()
View 9 Replies
Apr 3, 2009
I have a DataGridView1 populated by sql searches. On the rare occasion that nothing is returned, my app cannot make use of data so I'm trying to check for null values. My code below is not correct because IsDBNull is not a member of the of the DataGridView1.
If DataGridView1.SelectedRows(0).IsDBNull Then
MsgBox("Nothing to display")
Exit Sub
End If
View 3 Replies
Feb 15, 2012
Having problems with null dates in a mysql table. Have eventually found out that I can store a 'null' date in mysql as "0000-00-00" and I can run the 'insert' command to add a record to the mysql table. When I check on mysql workbench I can see the row has been inserted correctly and the date shows as "0000-00-00".However...When I try to load the table into a datagridview, I get an error = mysql Conversion Exception was unhandled = "Unable to convert MySQL date/time value to System.DateTime".
View 4 Replies
Feb 4, 2011
How to get if the datagridview has a seleted row or current row? Ex. If datagridview1.HasCurrentRow = False then Messagebox.show("Please select a row first prior to click "change" button.") end if
View 2 Replies
Jun 22, 2010
This post is continuation to the post which was posted by StatiX on Oct 23rd, 2007 regarding "Get The Selected row in DatagridView". [code]...
View 5 Replies
Jan 30, 2012
How to do that no one cell is selected in DataGridView at first moment? (There are some controls in my form before the DataGridView and I don't want that any element of DataGridView is selected when the form is loaded).
View 2 Replies
Dec 16, 2009
I build an agenda in access on the left you have column year and then the month an then you have columns from monday to satrday
what i would like to see is when i select a year in the combox all the rows in datagrid of the selected year to have the same color also i would like to do that with the selected month
View 1 Replies
Feb 24, 2009
iam new to windows application.iam working with datagridview in vb.net .how to update the selected row in datagridview.any one help me with this.
View 1 Replies
Jul 28, 2009
I have a data which is saved in textfile. when form load the data in text file will be load in datagridview. i want delete the selected row from the datagridview. I used this coding to delete.
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
Dim row As Integer
[code].....
View 17 Replies
Jul 26, 2009
I have a data which is saved in textfile. when form load the data in text file will be load in datagridview. i want delete the selected row from the datagridview. I used this coding to delete.
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
Dim row As Integer
[Code]....
"Rows cannot be programmatically removed unless the datagridview is data-bound to an IBindingList that support change notification and allows deletion."
I dont understand what is this error and how to solve this?
View 8 Replies
Jul 26, 2009
I have a data which is saved in textfile. when form load the data in text file will be load in datagridview. i want delete the selected row from the datagridview. I used this coding to delete.Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
Dim row As Integer Public selRow As New DataGridViewRow Dim index As Integer
index = DataGridView1.SelectedRows.Item(0).Index
selRow = DataGridView1.Rows.Item(index)
DataGridView1.Rows.Remove(selRow)
row = row - 1
End Sub
When i exucute this code it shows me error "Rows cannot be programmatically removed unless the datagridview is data-bound to an IBindingList that support change notification and allows deletion."I dont understand what is this error and how to solve this?
View 3 Replies
May 26, 2012
Is it possible to prevent any row in a grid from being highlighted? I'm familiar with the "SelectionMode" property. I manually add rows to a DGV and the 1st row is always highlighted. I'm trying to prevent this from happening.
View 2 Replies
Mar 5, 2010
I've problem about visual studio. I've 2 form in my project. lets say frmMain and frmLookUP. in frmLookup I put a datagridview to bind data that user search. I want show data that user selected in frmLookUp datagridview to frmMain.
View 1 Replies
