CODEWITHSUNDEEP
c#sqlwinformscheckboxdatagridview
GuaGua0308
GuaGua0308

Reputation: 131

Allow only one checkbox selected in DataGridView

I have a datagridview fill with data from database. The first column is a checkboxcolumn (data for this column retrieved from database is type BIT) and I want the user only check one. If the user select other one, the first one have to be unchecked.

I have seen a lot of code and none works.

What I could do?

Is a Winforms C# app with SQL SERVER.

Upvotes: 7

Views: 13373

Answers (8)

Praveen Mitta
Praveen Mitta

Reputation: 1508

To handle dataGridView_CellValueChanged event we must trigger dataGridView_CellContentClick event (which does not have checkboxes current state) will call CommitEdit. This will trigger dataGridView_CellValueChanged event where we can write our logic to check/uncheck checkboxes.

private void dataGridView_CellContentClick(object sender, 
    DataGridViewCellEventArgs e)
{
    dataGridView.CommitEdit(DataGridViewDataErrorContexts.Commit);
}


/// <summary>
/// This will be fired by CellContentClick event from above
/// </summary>
private void dataGridView_CellValueChanged(object sender, 
    DataGridViewCellEventArgs e)
{
   //0 is checkbox column index
   var columnIndex = 0;
    if (e.ColumnIndex == columnIndex )
   {      
      var isChecked = (bool)dataGridView.Rows[e.RowIndex].Cells[e.ColumnIndex].Value;
      if (isChecked)
      {
         foreach (DataGridViewRow row in dataGridView.Rows)
         {
            if (row.Index != e.RowIndex)
            {
               row.Cells[columnIndex].Value = !isChecked;
            }
         }
      }
   }
}


//Bind the events in the form designer
this.dataGridView.CellContentClick += new DataGridViewCellEventHandler(this.dataGridView_CellContentClick);
this.dataGridView.CellValueChanged += new DataGridViewCellEventHandler(this.dataGridView_CellValueChanged);

Upvotes: 0

Francesco Giossi
Francesco Giossi

Reputation: 170

Here is my answer based on data manipulation. You need a datagridview named DataGridView1 in the form and nothing else.

    DataTable dt;

    private void Form1_Load(object sender, EventArgs e)
    {
        dt = CreateDataTablePeople("People");
        
        BindingSource bs = new BindingSource();
        bs.DataSource = dt;
        dataGridView1.DataSource = bs;

        dt.ColumnChanging += Dt_ColumnChanging  ;
    }

    private void Dt_ColumnChanging(object sender, DataColumnChangeEventArgs e)
    {
        if (e.Column.ColumnName == "Abilitato")
        {
            bool b = Convert.ToBoolean(e.ProposedValue);
            if (!b)
            {
                e.ProposedValue = true;
                return;
            }
            dt.ColumnChanging -= Dt_ColumnChanging;
            for (int i = dt.Rows.Count - 1; i >= 0; i--)
            {
                if (dt.Rows[i]["Id"] != e.Row["Id"])
                {
                    dt.Rows[i]["Abilitato"] = false;
                    dt.Rows[i].EndEdit();
                }
                
            }
            
            dt.ColumnChanging += Dt_ColumnChanging;
            
        }
    }

    private DataTable CreateDataTablePeople(string TableName)
    {
        using (DataTable dt = new DataTable(TableName))
        {
            dt.Columns.Add("ID", typeof(int));
            dt.Columns.Add("Name", typeof(string));
            dt.Columns.Add("Abilitato", typeof(bool));

            dt.LoadDataRow(new object[] { 1, "Frank", false }, true);
            dt.LoadDataRow(new object[] { 2, "Michael", false}, true);
            dt.LoadDataRow(new object[] { 3, "Paul", false }, true);

            return dt;
        }
    }

    private void dataGridView1_CurrentCellDirtyStateChanged(object sender, EventArgs e)
    {
        DataGridViewDataErrorContexts ec = DataGridViewDataErrorContexts.Commit;
        DataGridView dg = (DataGridView)sender;
        bool b = dg.CommitEdit(ec);
    }

Upvotes: 0

senthilkumar2185
senthilkumar2185

Reputation: 2566

private void DataGridView_CellClick(object sender, DataGridViewCellEventArgs e)
{
    //Check to ensure that the row CheckBox is clicked.
    if (e.RowIndex >= 0 && e.ColumnIndex == 0)
    {
        //Loop and uncheck all other CheckBoxes.
        foreach (DataGridViewRow row in dataGridView1.Rows)
        {
            if (row.Index == e.RowIndex)
            {
                row.Cells["checkBoxColumn"].Value = !Convert.ToBoolean(row.Cells["checkBoxColumn"].EditedFormattedValue);
            }
            else
            {
                row.Cells["checkBoxColumn"].Value = false;
            }
        }
    }
}

Upvotes: 0

user11773629
user11773629

Reputation:

Here is a slightly cleaned-up version. My checkbox column is dynamically added and always the last column in the grid, but you get the idea:

    private void ProfilesGrid_CellContentClick(object sender, [NotNull] DataGridViewCellEventArgs e)
    {
        DataGridView dataGridView = (DataGridView)sender;

        int columnCount = dataGridView.Columns.GetColumnCount(DataGridViewElementStates.None) - 1;

        if (e.ColumnIndex != columnCount)
        {
            return;
        }

        dataGridView.EndEdit();

        if (!(bool) dataGridView[e.ColumnIndex, e.RowIndex].Value)
        {
            return;
        }

        foreach (DataGridViewRow row in dataGridView.Rows.Cast<DataGridViewRow>().Where(row => row.Index != e.RowIndex))
        {
            row.Cells[columnCount].Value = false;
        }
    }

Upvotes: 0

A Burns
A Burns

Reputation: 91

VB net version

Private Sub dataGridView_CellValueChanged(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DG_SubSyncs.CellValueChanged
    Dim columnIndex As Integer = 0
       If (e.ColumnIndex = columnIndex) Then
          'If the user checked this box, then uncheck all the other rows
          Dim isChecked As Boolean = CBool(DG_SubSyncs.Rows(e.RowIndex).Cells(e.ColumnIndex).Value)
           If (isChecked) Then
              For Each row In DG_SubSyncs.Rows
                  If (row.Index <> e.RowIndex) Then
                      row.Cells(columnIndex).Value = Not isChecked
                     End If
               Next
           End If
       End If
   End Sub

Upvotes: 0

Rychu
Rychu

Reputation: 995

Subscribe to CellContentClick and add dataGridView.EndEdit() for much better user experience (cell doesn't have to lose the focus for event to be fired):

private void ChangeCheckedStateOfOtherCheckboxesInDgv(object sender, DataGridViewCellEventArgs e)
{
    const int chkBoxColumnIndex = 0;

    var dataGridView = (DataGridView)sender;

    if (e.ColumnIndex == chkBoxColumnIndex)
    {
        dataGridView.EndEdit();

        var isChecked = (bool)dataGridView[e.ColumnIndex, e.RowIndex].Value;

        if (isChecked)
        {
            foreach (DataGridViewRow row in dataGridView.Rows)
            {
                if (row.Index != e.RowIndex)
                    row.Cells[chkBoxColumnIndex].Value = !isChecked;
            }
        }
    }
}

Upvotes: 2

Salih Karagoz
Salih Karagoz

Reputation: 2289

You have to set the VirtualMode setting to TRUE on the DGV to allow only one checkbox.

Upvotes: -1

Jon
Jon

Reputation: 3255

private void dataGridView_CellValueChanged(object sender, DataGridViewCellEventArgs e)
{
   // Whatever index is your checkbox column
   var columnIndex = 0;
   if (e.ColumnIndex == columnIndex)
   {
      // If the user checked this box, then uncheck all the other rows
      var isChecked = (bool)dataGridView.Rows[e.RowIndex].Cells[e.ColumnIndex].Value;
      if (isChecked)
      {
         foreach (DataGridViewRow row in dataGridView.Rows)
         {
            if (row.Index != e.RowIndex)
            {
               row.Cells[columnIndex].Value = !isChecked;
            }
         }
      }
   }
}

Upvotes: 4

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