[RESOLVED] Datagridview Select

[sukarno1234]

Im new with datagridview. . . .and i want to delete a certain row or the user will select a item in datagrid but im find it hard to do it. . . .here's my code hope that u can elp me with this. . . .

If dread.HasRows Then
                Dim cmd1 As New MySqlCommand("DELETE FROM product WHERE p_code = '" & listgrid.SelectedRows(0).Selected & "'", conn1)
                d = cmd1.ExecuteReader
                For Each row As DataGridViewRow In listgrid.SelectedRows
                    listgrid.Rows.Remove(row)
                Next
            End If

[make me rain]

listgrid.SelectedRows ??

so here if the row is selected then only the particular row should be removed
how the selected is identified, is there any check box column in it

[sukarno1234]

listgrid.SelectedRows ??

so here if the row is selected then only the particular row should be removed
how the selected is identified, is there any check box column in it

no there are no check box in my datagridview. . . .im new with datagrid. . . .can u show ho to delete it and will update datagrid??i have my database. . . .

[make me rain]

it is in your code

DELETE FROM product WHERE p_code = '" & listgrid.SelectedRows(0).Selected & "'", conn1)
                d = cmd1.ExecuteReader

after loading your data in to the datagridview
(1) you need to give a specific way to the user to select the row or rows
(2) one way of doing it is providing the check box columns in the grid
(3) and if the user selects any such row ( i mean if selected is true) then that row should be deleted from the database + from grid as well

so how you are populating your grid

[sukarno1234]

it is in your code

DELETE FROM product WHERE p_code = '" & listgrid.SelectedRows(0).Selected & "'", conn1)
                d = cmd1.ExecuteReader

after loading your data in to the datagridview
(1) you need to give a specific way to the user to select the row or rows
(2) one way of doing it is providing the check box columns in the grid
(3) and if the user selects any such row ( i mean if selected is true) then that row should be deleted from the database + from grid as well

so how you are populating your grid

can you at least show me how to do it . . . .

this is how i populate my grid. . . .

listgrid.Rows.Item(i).Cells(0).Value = txtquantity.Text
            listgrid.Rows.Item(i).Cells(1).Value = txtdsprod.Text
            listgrid.Rows.Item(i).Cells(2).Value = txtprice.Text
            listgrid.Rows.Item(i).Cells(3).Value = txtSubtotal.Text

[make me rain]

Ok wait a minute

[make me rain]

I don't know what & how you are doing the database operations, with out going in to that i am just showing the removing and adding of the rows in datagridview control

fins the attachment here with

[sukarno1234]

it was a useful information sir but i can edit the value of the datagrid how can i disable it without??when i disable it i cant click the remove item. . . .I have a database and i want to delete the selected rows and the user cant edit the datagrid. . . .

[make me rain]

put it in your form load event

With Me.DataGridView1
            .Columns(0).ReadOnly = True
            .Columns(1).ReadOnly = True
            .Columns(2).ReadOnly = True
            .Columns(3).ReadOnly = True
        End With

[sukarno1234]

it's working now. . . .but how could i do this with a database. . . .i have a database and i want to update the database everytime i delete a item in datagridview. . . .

[make me rain]

wait a minute

[make me rain]

fallow the steps
(1) add one more column in the attached datagridview control
(2) alter this sub routine as below

Private Sub Btn_drop_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Btn_drop.Click
 
        Dim I As Int16
        Dim ISrowSelected As Boolean
        Dim TTLrows As Int16
 
        Dim DeleteID As Long
 
        With Me.DataGridView1
            TTLrows = .RowCount - 1
            For I = TTLrows To 0 Step -1
 
                ISrowSelected = .Rows(I).Cells(5).Value
                DeleteID = .Rows(I).Cells(4).Value ' not here you need to specify 
                'which column containes the primary key / unique key value 
                'that is .Cells(4).value replace 4 accordingly
 
                If ISrowSelected = True Then
 
                    Call DelteDBrecord(DeleteID) ' this sub routine will delete records in database
                    'for editing you need to just alter your SQL
                    'That is SQL_drop variable in sub routine DelteDBrecord
                    'thats it
                    .Rows.Remove(.Rows(I))
                End If
            Next
        End With
    End Sub

(3) add this sub routine in to your project

Private Sub DelteDBrecord(ByVal uniqueValue As Long)
        'unique ID is may be a autonumber field
        'or the primary key column
 
        Dim SQL_drop As String = "DELETE FROM databnaseTable WHERE databnaseTable.FieldValue = @uniqueValue;"
 
        'create the MySQL command object as shown below with the proper arguments
        Dim CMD_drop As New mysqlcommand(SQL_drop, YourConnectionobject)
 
        With CMD_drop
            .parameters.addwithvalue("@uniqueValue", uniqueValue)
            'OpenAccess your connection here
            .executenonquery()
            'Close your connection here
            .dispose()
            'now this dewletes the vlues in database
            'the unique key (primary key is datagrid view column 5 value
        End With
 
    End Sub

if the post helps you please close the thread

[sukarno1234]

Thank you sir. . . I have a one last question how do i populate the datagrid with my data in my database programatically without using datasource of the datagrid. . . .Im new with datagrid hope that you can elp me sir . . . .

[sukarno1234]

Im confuse with this line what it means. . . .this is my 1st tym to encounter this. . . .can u explain it to me. . . .plzzzz. . . .

databnaseTable.FieldValue = @uniqueValue

[make me rain]

past this sub in any module or at the top of your form class

Public Sub FillGrid(ByVal DgV As DataGridView, ByVal SQL As String, ByVal DGVcol As Int16, Optional ByVal PARA As String = "")
        'intx
        'fills datagridview with / without criteria
 
 
        Dim WITHcry As Boolean
 
        If PARA Is Nothing OrElse PARA = "" Then
            WITHcry = False
        Else
            WITHcry = True
        End If
 
        Dim i, j As Integer
        Dim CMD_withCry As New MySqlCommand(SQL, yourconnectionObject)
 
        Dim Da_FillGrid As New MySqlDataAdapter(CMD_withCry)
        Dim Ds_FillGrid As New DataSet
 
        If WITHcry = True Then
            CMD_withCry.Parameters.AddWithValue("@PARA", PARA)
        End If
        open your connection here
        Da_FillGrid.Fill(Ds_FillGrid, "T1")
        close your connection here
 
        Dim cOLC As Int16 = DGVcol 'DgV.Columns.Count
        DgV.Rows.Clear()
 
        With Ds_FillGrid.Tables("T1")
            j = .Rows.Count
            GridFillerCount = j
            If j <= 0 Then
                Exit Sub
            Else
                DgV.Rows.Clear()
                DgV.Rows.Add(j)
 
                For i = 0 To cOLC - 1
                    For K = 0 To j - 1
                        DgV.Rows(K).Cells(i).Value = .Rows(K).Item(i).ToString
                    Next
                Next
            End If
        End With
 
        CMD_withCry.Dispose()
        Da_FillGrid.Dispose()
        Ds_FillGrid.Dispose()
 
 
    End Sub

this is how to fill the datagridview

Dim SQL_CurrentHolding As String = "SELECT * FROM current_hldg_grid;"
        Call FillGrid(Me.DGV_Holding, SQL_CurrentHolding, 8)
 
note here
'fill the arguments correctly
(1) SQL statement
(2) if your SQL statement is having any parameter then use it as
     (a) SELECT * FROM current_hldg_grid WHERE current_hldg_grid.username = @PARA;"
(2)pass your datagridview control name
(3) pass number of columns to fill for example 6 columns ( exclude check box column)
(4) pass the parameter value ( optional) if it is there in your SQL statement

[make me rain]

databnaseTable.FieldValue = @uniqueValue

this is the SQL statement , it is like a verb in english,
what it does is
for ex:
assume there is table by name usertable
and username is a field in table usertable

SELECT username from usertable;

this gives all the username in the table usertable

if you want to see a particular user in the table then the SYNTAX will be like

SELECT fieldname FROM tablename WHERE tablename.fieldname = 'SUKOI';

this means you are searching the table / looking for a record by criteria as 'SUKOI'

Accordingly when ever you are

fetching record
editng record
deleting record

you need to tell the SQL where exactly it should go & after going in to particular record what it should do

that is what is this

"DELETE FROM databnaseTable WHERE databnaseTable.FieldValue = @uniqueValue;"

because you don't know what is the @uniqueValue
it will be fetched while the application run, that is you are deleting only the rows which are selected by the user ( check box column)

so the @ indicates the parameter , & this will be passed during the runtime

that is waht this

With CMD_drop
            .parameters.addwithvalue("@uniqueValue", uniqueValue)

after passing the parameter you are executing the query
that is what this

.executenonquery()
            'Close your connection here

[sukarno1234]

thanks 4 the info make me rain. . . .u elp me alot. . . .

[make me rain]

Sukoi with out fail
you need to rate this good , bad meaning full, meaning less, understandable , hope less, outdated
etc....

this improves many thing on the forum