DataGridView.Columns Property

Reference

Definition

Namespace:: System.Windows.Forms

Assembly:: System.Windows.Forms.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Gets a collection that contains all the columns in the control.

public:
 property System::Windows::Forms::DataGridViewColumnCollection ^ Columns { System::Windows::Forms::DataGridViewColumnCollection ^ get(); };

public System.Windows.Forms.DataGridViewColumnCollection Columns { get; }

member this.Columns : System.Windows.Forms.DataGridViewColumnCollection

Public ReadOnly Property Columns As DataGridViewColumnCollection

Property Value

DataGridViewColumnCollection

The DataGridViewColumnCollection that contains all the columns in the DataGridView control.

Examples

The following code example demonstrates how to create an unbound DataGridView; set the ColumnHeadersVisible, ColumnHeadersDefaultCellStyle, and ColumnCount properties; and use the Rows and Columns properties. It also demonstrates how to use a version of the AutoResizeColumnHeadersHeight and AutoResizeRows methods to properly size the column headers and the rows. To run this example, paste the following code into a form that contains a DataGridView named dataGridView1 and a button named Button1, and then call the InitializeDataGridView method from the form's constructor or Load event handler. Ensure all events are connected with their event handlers.

   void InitializeDataGridView()
   {
      this->Size = System::Drawing::Size( 600, 600 );
      dataGridView1->Size = System::Drawing::Size( 450, 400 );

      // Create an unbound DataGridView by declaring a column count.
      dataGridView1->ColumnCount = 4;
      dataGridView1->ColumnHeadersVisible = true;

      // Set the column header style.
      DataGridViewCellStyle ^ columnHeaderStyle = gcnew DataGridViewCellStyle;
      columnHeaderStyle->BackColor = Color::Aqua;
      columnHeaderStyle->Font = gcnew System::Drawing::Font( "Verdana",10,FontStyle::Bold );
      dataGridView1->ColumnHeadersDefaultCellStyle = columnHeaderStyle;

      // Set the column header names.
      dataGridView1->Columns[ 0 ]->Name = "Recipe";
      dataGridView1->Columns[ 1 ]->Name = "Category";
      dataGridView1->Columns[ 2 ]->Name = "Main Ingredients";
      dataGridView1->Columns[ 3 ]->Name = "Rating";

      // Populate the rows.
      array<String^>^row1 = gcnew array<String^>{
         "Meatloaf","Main Dish","ground beef","**"
      };
      array<String^>^row2 = gcnew array<String^>{
         "Key Lime Pie","Dessert","lime juice, evaporated milk","****"
      };
      array<String^>^row3 = gcnew array<String^>{
         "Orange-Salsa Pork Chops","Main Dish","pork chops, salsa, orange juice","****"
      };
      array<String^>^row4 = gcnew array<String^>{
         "Black Bean and Rice Salad","Salad","black beans, brown rice","****"
      };
      array<String^>^row5 = gcnew array<String^>{
         "Chocolate Cheesecake","Dessert","cream cheese","***"
      };
      array<String^>^row6 = gcnew array<String^>{
         "Black Bean Dip","Appetizer","black beans, sour cream","***"
      };
      array<Object^>^rows = {row1,row2,row3,row4,row5,row6};
      System::Collections::IEnumerator^ myEnum = rows->GetEnumerator();
      while ( myEnum->MoveNext() )
      {
         array<String^>^rowArray = safe_cast<array<String^>^>(myEnum->Current);
         dataGridView1->Rows->Add( rowArray );
      }
   }

   void Button1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      // Resize the height of the column headers. 
      dataGridView1->AutoResizeColumnHeadersHeight();

      // Resize all the row heights to fit the contents of all non-header cells.
      dataGridView1->AutoResizeRows(
            DataGridViewAutoSizeRowsMode::AllCellsExceptHeaders);
   }

   void InitializeContextMenu()
   {
      // Create the menu item.
      MenuItem^ getRecipe = gcnew MenuItem( "Search for recipe",gcnew System::EventHandler( this, &Form1::OnMenuClick ) );

      // Add the menu item to the shortcut menu.
      System::Windows::Forms::ContextMenuStrip^ recipeMenu = gcnew System::Windows::Forms::ContextMenuStrip();

      // Set the shortcut menu for the first column.
      dataGridView1->Columns[ 0 ]->ContextMenuStrip = recipeMenu;
   }

   void OnMenuClick( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      if ( dataGridView1->CurrentCell != nullptr )
      {
         //Retrieve the recipe name.
         String^ recipeName = dynamic_cast<String^>(dataGridView1->CurrentCell->Value);

         //Search for the recipe.
         System::Diagnostics::Process::Start( String::Format( "http://search.msn.com/results.aspx?q={0}", recipeName ), nullptr );
      }
   }

private:

private void InitializeDataGridView()
{
    // Create an unbound DataGridView by declaring a column count.
    dataGridView1.ColumnCount = 4;
    dataGridView1.ColumnHeadersVisible = true;

    // Set the column header style.
    DataGridViewCellStyle columnHeaderStyle = new DataGridViewCellStyle();

    columnHeaderStyle.BackColor = Color.Beige;
    columnHeaderStyle.Font = new Font("Verdana", 10, FontStyle.Bold);
    dataGridView1.ColumnHeadersDefaultCellStyle = columnHeaderStyle;

    // Set the column header names.
    dataGridView1.Columns[0].Name = "Recipe";
    dataGridView1.Columns[1].Name = "Category";
    dataGridView1.Columns[2].Name = "Main Ingredients";
    dataGridView1.Columns[3].Name = "Rating";

    // Populate the rows.
    string[] row1 = new string[] { "Meatloaf", "Main Dish", "ground beef",
        "**" };
    string[] row2 = new string[] { "Key Lime Pie", "Dessert", 
        "lime juice, evaporated milk", "****" };
    string[] row3 = new string[] { "Orange-Salsa Pork Chops", "Main Dish", 
        "pork chops, salsa, orange juice", "****" };
    string[] row4 = new string[] { "Black Bean and Rice Salad", "Salad", 
        "black beans, brown rice", "****" };
    string[] row5 = new string[] { "Chocolate Cheesecake", "Dessert", 
        "cream cheese", "***" };
    string[] row6 = new string[] { "Black Bean Dip", "Appetizer", 
        "black beans, sour cream", "***" };
    object[] rows = new object[] { row1, row2, row3, row4, row5, row6 };

    foreach (string[] rowArray in rows)
    {
        dataGridView1.Rows.Add(rowArray);
    }
}

private void button1_Click(object sender, System.EventArgs e)
{
    // Resize the height of the column headers. 
    dataGridView1.AutoResizeColumnHeadersHeight();

    // Resize all the row heights to fit the contents of all non-header cells.
    dataGridView1.AutoResizeRows(
        DataGridViewAutoSizeRowsMode.AllCellsExceptHeaders);
}

private void InitializeContextMenu()
{
    // Create the menu item.
    ToolStripMenuItem getRecipe = new ToolStripMenuItem("Search for recipe", null,
        new System.EventHandler(ShortcutMenuClick));

    // Add the menu item to the shortcut menu.
    ContextMenuStrip recipeMenu = new ContextMenuStrip();
    recipeMenu.Items.Add(getRecipe); 

    // Set the shortcut menu for the first column.
    dataGridView1.Columns[0].ContextMenuStrip = recipeMenu;
    dataGridView1.MouseDown += new MouseEventHandler(dataGridView1_MouseDown);
}

private DataGridViewCell clickedCell;

private void dataGridView1_MouseDown(object sender, MouseEventArgs e)
{
// If the user right-clicks a cell, store it for use by the shortcut menu.
    if (e.Button == MouseButtons.Right)
    {
        DataGridView.HitTestInfo hit = dataGridView1.HitTest(e.X, e.Y);
        if (hit.Type == DataGridViewHitTestType.Cell)
        {
            clickedCell =
                dataGridView1.Rows[hit.RowIndex].Cells[hit.ColumnIndex];
        }
    }
}

private void ShortcutMenuClick(object sender, System.EventArgs e)
{
    if (clickedCell != null)
    {
        //Retrieve the recipe name.
        string recipeName = (string)clickedCell.Value;

        //Search for the recipe.
        System.Diagnostics.Process.Start(
            "http://search.msn.com/results.aspx?q=" + recipeName);
            //null);
    }
}

Private Sub InitializeDataGridView()

    ' Create an unbound DataGridView by declaring a column count.
    dataGridView1.ColumnCount = 4
    dataGridView1.ColumnHeadersVisible = True

    ' Set the column header style.
    Dim columnHeaderStyle As New DataGridViewCellStyle()

    columnHeaderStyle.BackColor = Color.Beige
    columnHeaderStyle.Font = New Font("Verdana", 10, FontStyle.Bold)
    dataGridView1.ColumnHeadersDefaultCellStyle = columnHeaderStyle

    ' Set the column header names.
    dataGridView1.Columns(0).Name = "Recipe"
    dataGridView1.Columns(1).Name = "Category"
    dataGridView1.Columns(2).Name = "Main Ingredients"
    dataGridView1.Columns(3).Name = "Rating"

    ' Populate the rows.
    Dim row1() As String = {"Meatloaf", "Main Dish", "ground beef", "**"}
    Dim row2() As String = _
        {"Key Lime Pie", "Dessert", "lime juice, evaporated milk", "****"}
    Dim row3() As String = {"Orange-Salsa Pork Chops", "Main Dish", _
        "pork chops, salsa, orange juice", "****"}
    Dim row4() As String = {"Black Bean and Rice Salad", "Salad", _
        "black beans, brown rice", "****"}
    Dim row5() As String = _
        {"Chocolate Cheesecake", "Dessert", "cream cheese", "***"}
    Dim row6() As String = _
        {"Black Bean Dip", "Appetizer", "black beans, sour cream", "***"}
    Dim rows() As Object = {row1, row2, row3, row4, row5, row6}

    Dim rowArray As String()
    For Each rowArray In rows
        dataGridView1.Rows.Add(rowArray)
    Next rowArray

End Sub

Private Sub button1_Click(ByVal sender As Object, _
    ByVal e As System.EventArgs) Handles button1.Click

    ' Resize the height of the column headers. 
    dataGridView1.AutoResizeColumnHeadersHeight()

    ' Resize all the row heights to fit the contents of all 
    ' non-header cells.
    dataGridView1.AutoResizeRows( _
        DataGridViewAutoSizeRowsMode.AllCellsExceptHeaders)

End Sub

Private Sub InitializeContextMenu()

    ' Create the menu item.
    Dim getRecipe As New ToolStripMenuItem( _
        "Search for recipe", Nothing, AddressOf ShortcutMenuClick)

    ' Add the menu item to the shortcut menu.
    Dim recipeMenu As New ContextMenuStrip()
    recipeMenu.Items.Add(getRecipe)

    ' Set the shortcut menu for the first column.
    dataGridView1.Columns(0).ContextMenuStrip = recipeMenu

End Sub

Private clickedCell As DataGridViewCell

Private Sub dataGridView1_MouseDown(ByVal sender As Object, _
    ByVal e As MouseEventArgs) Handles dataGridView1.MouseDown

    ' If the user right-clicks a cell, store it for use by the 
    ' shortcut menu.
    If e.Button = MouseButtons.Right Then
        Dim hit As DataGridView.HitTestInfo = _
            dataGridView1.HitTest(e.X, e.Y)
        If hit.Type = DataGridViewHitTestType.Cell Then
            clickedCell = _
                dataGridView1.Rows(hit.RowIndex).Cells(hit.ColumnIndex)
        End If
    End If

End Sub

Private Sub ShortcutMenuClick(ByVal sender As Object, _
    ByVal e As System.EventArgs)

    If (clickedCell IsNot Nothing) Then
        'Retrieve the recipe name.
        Dim recipeName As String = CStr(clickedCell.Value)

        'Search for the recipe.
        System.Diagnostics.Process.Start( _
            "http://search.msn.com/results.aspx?q=" + recipeName)
    End If

End Sub

Remarks

By using the DataGridViewColumnCollection returned by this property, you can add columns, remove columns, and obtain a count of the columns contained in the DataGridView control. For more information, see DataGridViewColumnCollection.

Applies to

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