So, I simply need to fill a DataGridView of a WinForm with the result of a SQL request that I tried in MySQL Workbench and works perfectly.
It's not the first time I'm doing this in this particular program and all the others worked fine. However, no matter what I do, the DataGridView stays empty.
Here goes my code :
Dim BindingName As New BindingSource, ProdSet As New DataTable
Private Sub SelectAllFacture()
ClassConfig.Connexion.Open()
ProdSet.Clear()
Dim Requete As String
Requete = "SELECT * FROM Product"
Try
Dim Cmd As New MySqlCommand
With Cmd
.Connection = ClassConfig.Connexion
.CommandText = Requete
End With
Dim Adpt As New MySqlDataAdapter(Cmd)
Adpt.Fill(ProdSet)
Catch ex As Exception
Autorisations.ErrorCheck(ex)
End Try
ClassConfig.Connexion.Close()
BindingName.DataSource = ProdSet
DataGridView.DataSource = BindingName
End Sub
To explicit what is not shown :
DataGridView is ... well, the DataGridView
Autorisations.ErrorCheck(ex) calls a Sub from another class that opens a MsgBox on error (It doesn't).
ClassConfig.Connexion is simply the connection, stored in another Class
Instead of Filling a Dataset (prodset), make it a datatable
Dim prdtable as new DataTable
then
Adpt.Fill(prdtable)
BindingName.DataSource = prdtable
Also make sure you have either already added the correct columns to the DataGridView or set:
dataGridView.AutoGenerateColumns = true
Have been working always with SQLDataAdapter and Fill command for data fetching querys and with executenonquery for insert, update, delete ones.
I'm having a problem and can{t figure out what am I doing wrong.
I have a DataTable bind to a RadGrid. The DataTable gets the data for one particular month of a companys receipts and generates an extra column with info we need.
I get a selected month fron a RadControl and send the data after pressing a button:
Protected Sub RadButton1_Click(sender As Object, e As EventArgs) Handles RadButton1.Click
Dim fecha As Date
fecha = RadMonthYearPicker1.DbSelectedDate
miDataTable = objOPRecibo.FacturasEspeciales(fecha.Month, fecha.Year)
RadGrid1.Rebind()
End Sub
This is the function in the called object:
Public Function FacturasEspeciales(Mes As Integer, Anio As Integer) As DataTable
Dim FEDataTable As New DataTable
Using conection As New SqlConnection(constr)
Using cmd As New SqlCommand(#"SELECT
SUM(Det_Recibo.dCantidad) Cantidad,
Producto.Nombre,
SUM(Det_Recibo.mTotal) Valor,
SUM((((Det_Recibo.mTotal*100)/95)*1.12)) ESPE
FROM Det_Recibo
INNER JOIN Enc_Recibo
ON Det_Recibo.idRecibo = Enc_Recibo.idRecibo
INNER JOIN Producto
ON Det_Recibo.idProducto = Producto.IdProducto
WHERE MONTH(Enc_Recibo.dFechaFact)=#Mes AND
YEAR(Enc_Recibo.dFechaFact)=#Anio
Producto.idGasto = 1 OR Producto.idGasto = 2
GROUP BY Producto.Nombre")
cmd.Parameters.AddWithValue("#Mes", Mes)
cmd.Parameters.AddWithValue("#Anio", Anio)
Dim sda As New SqlDataAdapter(cmd.CommandText, conection)
sda.Fill(FEDataTable)
End Using
End Using
'Return DataTable
Return FEDataTable
End Function
I{m getting either a not defined scalar error for #Mes or a second error not specific about the sda.Fill line.
I´m sort of a newbie and after hours of research I just can´t figure out what am I doing wrong.
Any help would be apreciated
It is probably because of the missing connection.Open()
Using conection As New SqlConnection(constr)
conection.open()
<REST OF YOUR CODE>
Once again i am turning to you for help. I am a little stuck when trying to save data entered in a DataGridView back to the SQL table.
I have followed a number of posts but just cant seam to figure it out
I declare the following variables globally on the form
Dim SQLAdaptor As New SqlClient.SqlDataAdapter
Dim Con As New SqlClient.SqlConnection
Dim builder As SqlClient.SqlCommandBuilder
I call this when the form loads
Private Sub SetTicketList()
Con.ConnectionString = CropTrackMod.strConn
SQLAdaptor.SelectCommand = New SqlClient.SqlCommand("SELECT StockRef, Weight, EstimatedPrice, EstimatedPrice, DespatchedQuantity, EstimatedTransport, EstimatedLineTotal FROM TicketDetail", Con)
builder = New SqlClient.SqlCommandBuilder(SQLAdaptor)
Con.Open()
Dim myTable As DataTable = New DataTable
SQLAdaptor.Fill(myTable)
dgvTicketDetail.DataSource = myTable
End Sub
I call this when the user leaves a row on the data grid view which should save back to the sql table
Private Sub dgvTicketDetail_RowLeave
' at grid save'
Dim myTable = CType(dgvTicketDetail.DataSource, DataTable)
SQLAdaptor.Update(myTable)
End Sub
When the form is loaded the data grid view is populated with the correct columns so i think that the first part is ok. The problem comes when saving the data back. When I run it the first time there is no error message. When I try a second row I get the following error:
Update requires a valid InsertCommand when passed DataRow collection with new rows.
From what I can figure the problem is generated because there is no update command set on the data adaptor.
I've tried -
DataGridView1.DataSource=Nothing
and
DataGridView1.DataSource=Nothing
DataGridView1.Refresh()
and
DataGridView1.RefreshEdit()
None of them works..
I've written a method that sets the DataSource of the DataGridView when executed. but each time i execute it, it replicates the data with new value and appends it to the previous contents of the DGV.. I wanna clear the content and then add the values.. Is that possible?
If the DataGridView is bound to any datasource, you'll have to set the DataGridView's DataSource property to Nothing.
If the DataGridView is not bound to any data source, this code will do the trick:
DataGridView.Rows.Clear()
For unbound cases note that:
DataGridView.Rows.Clear()
leaves the Columns collection in place.
DataGridView.Columns.Clear()
..will remove all the columns and rows. If you are using the DGV unbound, and on next use the columns change, clearing the Rows may not be adequate. For library code clear all the columns before adding columns.
I'd probably use this...
DataGridView1.Rows.Clear()
to clear out the rows and then rebind.
Follow the easy way like this
assume that ta is a DataTable
ta.clear()
DataGridView1.DataSource = ta
DataGridView1.DataSource = Nothing
Can you not bind the datagridview to an empty collection (instead of null). That do the trick?
To remove the old record in datagridview when you are searching for new result,with button_click event write the following code,
me.DataGridview1.DataSource.clear()
this code will help to remove the old record in datagridview.
I found that setting the datasource to null removes the columns. This is what works for me:
c#:
((DataTable)myDataGrid.DataSource).Rows.Clear();
VB:
Call CType(myDataGrid.DataSource, DataTable).Rows.Clear()
My DataGridView is also bound to a DataSource and myDataGridView.Columns.Clear() worked fine but myDataGridView.Rows.Clear() did NOT. Just an FYI for those who have tried .Rows.
Don't do anything on DataGridView, just clear the data source. I tried clearing myDataset.clear() method, then it worked.
I've got this code working in a windows form,
Public Class Form1
Private dataStuff As List(Of String)
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
DataGridView1.DataSource = Nothing
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
dataStuff = New List(Of String)
dataStuff.Add("qwerty")
dataStuff.Add("another")
dataStuff.Add("...and another")
DataGridView1.DataSource = dataStuff
End Sub
End Class
You should remove the table from dataset if the datagrid is bind to some datatable. Your Gridview will be cleared automatically. No other way.
[YourDatasetName].Tables.Clear()
I had the same problem on gridview content clearing. The datasource i used was a datatable having no columns, and i added columns and rows programmatically to datatable. Then bind to datagridview. I tried the code related with gridview like gridView.Rows.Clear(), gridView.DataSource = Nothing
but it didn't work for me. Then try the below code related with datatable before binding it to datagridview each time.
dtStore.Rows.Clear()
dtStore.Columns.Clear()
gridView.DataSource = dtStore
And is working fine, no replication in DataGridView
1) create button named it Clear.Inside insert tfhe following code
datagridviewer.DataSource=nothing
2) In your search button begin your code by the following statement
datagridviewer.DataSource = DataSet.table
Nb:instead of table put the real name of your table
ex: datagridviewer.DataSource = DataSet.client
When feeding info from an SQL query into a datagridview you can clear the datagridview first before reloading it.
Where I have defined dbDataSet as New DataTable I can do a clear.
dbDataSet must be at the start of the form within the Public Class Form
Dim dbDataset AS New DataTable
within the code of you Private Sub, place
dbDataSet.Clear()
You may have a user scenario such that you want to keep the data binding and only temporarily clear the DataGridView. For instance, you have the user click on a facility on a map to show its attributes for editing. He is clicking for the first time, or he has already clicked on one and edited it. When the user clicks the "Select Facility" button, you would like to clear the DataGridView of the data from the previous facility (and not throw an error if it's his first selection). In this scenario, you can achieve the clean DataGridView by adapting the generated code that fills the DataGridView. Suppose the generated code looks like this:
Try
Me.Fh_maintTableAdapter.FillByHydrantNumber(Me.Fh2010DataSet.fh_maint, hydrantNum)
Catch ex As System.Exception
System.Windows.Forms.MessageBox.Show(ex.Message)
End Try
We are filling the DataGridView based on the hydrant number. Copy this code to the point where you want to clear the DataGridView and substitute a value for "hydrantNum" that you know will retrieve no data. The grid will clear. And when the user actually selects a facility (in this case, a hydrant), the binding is in place to fill the DataGridView appropriately.
If the DataGridView is bound to any datasource,
DataGridView1.DataSource = Nothing
DataGridView1.DataBind()
Dim DS As New DataSet
DS.Clear() - DATASET clear works better than DataGridView.Rows.Clear() for me :
Public Sub doQuery(sql As String)
Try
DS.Clear() '<-- here
' - CONNECT -
DBCon.Open()
' Cmd gets SQL Query
Cmd = New OleDbCommand(sql, DBCon)
DA = New OleDbDataAdapter(Cmd)
DA.Fill(DS)
' - DISCONNECT -
DBCon.Close()
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
If the GridView (Say the name is gvArchive) is bound to any DataSource, the following will clear it:
gvArchive.DataSource = Nothing
gvArchive.DataBind()
just write this
DataGridView1.DataSource = ""
I had the same problem: I was programmatically binding my GridView1 to one SQL table [dictonary] or another [meny] BUT when I selected the second table from my RadioButtonList1, I was getting an error (System.Web.HttpException: Field or property with the title [the first column's title from the previously selected table] was not found in the selected data source.) i.e. saying that the columns from my first-selected table couldn't be found. All I needed to do was insert:
GridView1.Columns.Clear()
before adding the table columns. Here goes the full code:
Dim connectionString As String = "your-string-details"
Dim connection As New SqlConnection(connectionString)
Then comes your first Sub:
Private Sub BindOrders()
connection.Open()
Dim sqlCommand As String = "SELECT * FROM [dictionary]"
Dim dataAdapter As New SqlDataAdapter(sqlCommand, connection)
Dim dt As New DataTable()
dataAdapter.Fill(dt)
GridView1.Columns.Clear() ' clear columns before adding new ones
If GridView1.Columns.Count <= 0 Then
Dim Field As New BoundField()
Field.DataField = "id"
Field.HeaderText = "id"
GridView1.Columns.Add(Field)
Field = New BoundField()
Field.DataField = "strArHundreds"
Field.HeaderText = "strArHundreds"
GridView1.Columns.Add(Field)
Field = New BoundField()
Field.DataField = "strArTens"
Field.HeaderText = "strArTens"
GridView1.Columns.Add(Field)
Field = New BoundField()
Field.DataField = "strArSingles"
Field.HeaderText = "strArSingles"
GridView1.Columns.Add(Field)
End If
GridView1.DataSource = dt
GridView1.DataBind()
connection.Close()
End Sub
Then comes your second Sub:
Private Sub BindDocuments()
connection.Open()
Dim sqlCommand As String = "SELECT * FROM [meny]"
Dim dataAdapter As New SqlDataAdapter(sqlCommand, connection)
Dim dt As New DataTable()
dataAdapter.Fill(dt)
GridView1.Columns.Clear() ' clear columns before adding new ones
If GridView1.Columns.Count <= 0 Then
Dim Field As New BoundField
Field = New BoundField
Field.DataField = "id"
Field.HeaderText = "id"
GridView1.Columns.Add(Field)
Field = New BoundField
Field.DataField = "nazev"
Field.HeaderText = "nazev"
GridView1.Columns.Add(Field)
End If
GridView1.DataSource = dt
GridView1.DataBind()
connection.Close()
End Sub
Finally comes your RadioButton:
Protected Sub RadioButtonList1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles RadioButtonList1.SelectedIndexChanged
Dim index As Integer
index = RadioButtonList1.SelectedIndex
Select Case index
Case 0
BindOrders()
Exit Select
Case 1
BindDocuments()
Exit Select
End Select
End Sub
For completion, here is the code for the GridView1 and the RadioButtonList1 in the associated aspx.file:
<asp:RadioButtonList ID="RadioButtonList1"
runat="server"
AutoPostBack="True"
OnSelectedIndexChanged="RadioButtonList1_SelectedIndexChanged">
<asp:ListItem>Obraty</asp:ListItem>
<asp:ListItem>Dokumenty</asp:ListItem>
</asp:RadioButtonList>
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False">
</asp:GridView>
This all works well now.
The mistake that you are making is that you seem to be using a dataset object for storing your data. Each time you use the following code to put data into your dataset you add data to the data already in your dataset.
myDataAdapter.Fill(myDataSet)
If you assign the table in your dataset to a DataGridView object in your program by the following code you will get duplicate results because you have not cleared data which is already residing in your dataset and in your dataset table.
myDataGridView.DataSource = myDataSet.Tables(0)
To avoid replicating the data you have to call clear method on your dataset object.
myDataSet.clear()
An then assign the table in your dataset to your DataGridView object.
The code is like this.
myDataSet.clear()
myDataAdapter.Fill(myDataSet)
myDataGridView.DataSource = myDataSet.Tables(0)
You can try this code:
' clear previous data
DataGridView2.DataSource = Nothing
DataGridView2.DataMember = Nothing
DataGridView2.Refresh()
Try
connection.Open()
adapter1 = New SqlDataAdapter(sql, connection)
' clear data already in the dataset
ds1.Clear()
adapter1.Fill(ds1)
DataGridView2.DataSource = ds1.Tables(0)
connection.Close()
Catch ex As Exception
MsgBox(ex.ToString)
End Try
Use this code where ever you want to implement clear datagridview command
datagridview1.datasource= nothing
datagridview1.datasource= ds
dt.clear() 'Dt as new DATATABLE
ds.clear() 'Ds as new Dataset
this code will clear the datagridview and wil stop data duplication when populating data from database.
You can do in this way:
DataGridView1.Enable = false
DataGridView1.DataSource = Nothing
DataGridView1.Enable = true
For the Clear of Grid View Data You Have to clear the dataset or Datatable
I use this Code I clear the Grid View Data even if re submit again and again it will work
Example
Dim con As New OleDbConnection
Dim cmd As New OleDbCommand
Dim da As New OleDbDataAdapter
Dim dar As OleDbDataReader
Dim dt As New DataTable
If (con.State <> 1) Then
con.Open()
End If
dt.Clear() 'To clear Data Every time to fresh data
cmd.Connection = con
cmd.CommandText = "select * from users"
da.SelectCommand = cmd
da.Fill(dt)
DataGridView1.DataSource = dt
DataGridView1.Visible = True
cmd.Dispose()
con.Close()
You can do that only by the following 2 lines:
DataGridView1.DataSource=Nothing
DataGridView1.DataBind()
You can also try this code if you want to clear all data in your DataGridView
DataGridView1.DataSource.Clear()
Try this for a specific cell:
Datagrid.Rows(RowIndex).Cells(ColIndex).Value = DBNull.Value
DgRemolques is the name of my Data grid on WPF
dgRemolques.ItemsSource = Nothing
but i need to clean also de DataTable
dtRemolques.Clear()
I am working in VB.NET and I have a simple requirement:
I have added a MDB file to a DataSet and it contains 21 tables.
I have a DataGridView and a ComboBox on my form.
I was able to get the ComboBox populated with the table names available in the DataSet by iterating through dataset.Tables.
Now I want to the user to be able to select the table name from the ComboBox and then populate the contents of that table.
I tried the following code:
Datagridview1.DataSource = dataset1
Datagridview1.DataMember = dataset1.tables(combobox1.selecteditem)
Datagridview1.Refresh()
But I only got the column headers. Then I read that I need a TableAdapter to populate the DataSet with that table. But if I use the TableAdapter then I won't be able to populate the table in a generic way.
Currently if I have to populate TableA then I will have to create an instance of Dataset1TableAdapters.TableA and then use it's .Fill property to populate the table. I will also have to use "Dataset1TableAdapters.TableB`. Is there a generic method to populate any table in the DataSet?
The following worked for me:
Datagridview1.DataSource = dataset1.tables(combobox1.selecteditem)
C# but easily convertible to VB.Net (I suppose):
String connectionString = #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=""C:\test.mdb""";
String tableName = combobox1.SelectedItem.ToString();
String sqlSELECT = String.Format("select * from [{0}]", tableName);
System.Data.OleDb.OleDbDataAdapter da = new System.Data.OleDb.OleDbDataAdapter();
da.SelectCommand = new System.Data.OleDb.OleDbCommand(sqlSELECT, new System.Data.OleDb.OleDbConnection(connectionString));
DataGridView1.DataSource = dataSet1;
DataGridView1.DataMember = dataSet1.Tables(tableName);
da.Fill(dataSet1, tableName);
I was just sketching a proof that "it can be done in a generic way" to your problem, you should elaborate and maybe come with something more elegant (and safe).
Private Sub BindData()
With customersDataGridView
.AutoGenerateColumns = True
.DataSource = customersDataSet
.DataMember = "Customers"
End With
End Sub
Just to clarify this answer. For Future Reference.
Public Class Form1
Dim con As OleDbConnection = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\test.accdb;")
Private Sub Button1_Click
Dim da As New OleDbDataAdapter
Dim table As String = ComboBox1.SelectedItem.ToString
Dim sql As String = String.Format("select * from [{0}]", table)
da.SelectCommand = New OleDbCommand(sql, con)
DataGridView1.DataSource = DataSet.Tables(table)
da.Fill(DataSet, table)
End Sub
End Class
Not trying to Ressurect, but i thought the working version of this VB Script should be posted.
I would like to point out that the dataset is held by Visual Studio, hence the strange source string.