DataGridViewComboBoxColumn.DataSource Properti

Definisi

Ruang nama:

System.Windows.Forms

Rakitan:

System.Windows.Forms.dll

Sumber:

DataGridViewComboBoxColumn.cs

Mendapatkan atau mengatur sumber data yang mengisi pilihan untuk kotak kombo.

public:
 property System::Object ^ DataSource { System::Object ^ get(); void set(System::Object ^ value); };

public object? DataSource { get; set; }

member this.DataSource : obj with get, set

Public Property DataSource As Object

Nilai Properti

Object

Objek yang mewakili sumber data. Defaultnya adalah null.

Pengecualian

InvalidOperationException

Nilai CellTemplate properti adalah null.

Contoh

Contoh kode berikut menunjukkan cara menggunakan DataGridViewComboBoxColumn untuk membantu memasukkan data ke TitleOfCourtesy dalam kolom. Properti DataSource digunakan untuk mengisi kotak kombo dengan pilihan judul. Contoh ini adalah bagian dari contoh yang lebih besar yang tersedia dalam DataGridViewComboBoxColumn topik gambaran umum kelas.

private:
    DataGridViewComboBoxColumn^ CreateComboBoxColumn()
    {
        DataGridViewComboBoxColumn^ column =
            gcnew DataGridViewComboBoxColumn();
        {
            column->DataPropertyName = ColumnName::TitleOfCourtesy.ToString();
            column->HeaderText = ColumnName::TitleOfCourtesy.ToString();
            column->DropDownWidth = 160;
            column->Width = 90;
            column->MaxDropDownItems = 3;
            column->FlatStyle = FlatStyle::Flat;
        }
        return column;
    }

private:
    void SetAlternateChoicesUsingDataSource(DataGridViewComboBoxColumn^ comboboxColumn)
    {
        {
            comboboxColumn->DataSource = RetrieveAlternativeTitles();
            comboboxColumn->ValueMember = ColumnName::TitleOfCourtesy.ToString();
            comboboxColumn->DisplayMember = comboboxColumn->ValueMember;
        }
    }

private:
    DataTable^ RetrieveAlternativeTitles()
    {
        return Populate("SELECT distinct TitleOfCourtesy FROM Employees");
    }

    String^ connectionString;

private:
    DataTable^ Populate(String^ sqlCommand)
    {
        SqlConnection^ northwindConnection = gcnew SqlConnection(connectionString);
        northwindConnection->Open();

        SqlCommand^ command = gcnew SqlCommand(sqlCommand, northwindConnection);
        SqlDataAdapter^ adapter = gcnew SqlDataAdapter();
        adapter->SelectCommand = command;

        DataTable^ table = gcnew DataTable();
        adapter->Fill(table);

        return table;
    }

    // Using an enum provides some abstraction between column index
    // and column name along with compile time checking, and gives
    // a handy place to store the column names.
    enum class ColumnName
    {
        EmployeeID,
        LastName,
        FirstName,
        Title,
        TitleOfCourtesy,
        BirthDate,
        HireDate,
        Address,
        City,
        Region,
        PostalCode,
        Country,
        HomePhone,
        Extension,
        Photo,
        Notes,
        ReportsTo,
        PhotoPath,
        OutOfOffice
    };

private DataGridViewComboBoxColumn CreateComboBoxColumn()
{
    DataGridViewComboBoxColumn column =
        new DataGridViewComboBoxColumn();
    {
        column.DataPropertyName = ColumnName.TitleOfCourtesy.ToString();
        column.HeaderText = ColumnName.TitleOfCourtesy.ToString();
        column.DropDownWidth = 160;
        column.Width = 90;
        column.MaxDropDownItems = 3;
        column.FlatStyle = FlatStyle.Flat;
    }
    return column;
}

private void SetAlternateChoicesUsingDataSource(DataGridViewComboBoxColumn comboboxColumn)
{
    {
        comboboxColumn.DataSource = RetrieveAlternativeTitles();
        comboboxColumn.ValueMember = ColumnName.TitleOfCourtesy.ToString();
        comboboxColumn.DisplayMember = comboboxColumn.ValueMember;
    }
}

private DataTable RetrieveAlternativeTitles()
{
    return Populate("SELECT distinct TitleOfCourtesy FROM Employees");
}

string connectionString =
    "Integrated Security=SSPI;Persist Security Info=False;" +
    "Initial Catalog=Northwind;Data Source=localhost";

private DataTable Populate(string sqlCommand)
{
    SqlConnection northwindConnection = new SqlConnection(connectionString);
    northwindConnection.Open();

    SqlCommand command = new SqlCommand(sqlCommand, northwindConnection);
    SqlDataAdapter adapter = new SqlDataAdapter();
    adapter.SelectCommand = command;

    DataTable table = new DataTable();
    table.Locale = System.Globalization.CultureInfo.InvariantCulture;
    adapter.Fill(table);

    return table;
}

// Using an enum provides some abstraction between column index
// and column name along with compile time checking, and gives
// a handy place to store the column names.
enum ColumnName
{
    EmployeeId,
    LastName,
    FirstName,
    Title,
    TitleOfCourtesy,
    BirthDate,
    HireDate,
    Address,
    City,
    Region,
    PostalCode,
    Country,
    HomePhone,
    Extension,
    Photo,
    Notes,
    ReportsTo,
    PhotoPath,
    OutOfOffice
};

Private Function CreateComboBoxColumn() _
    As DataGridViewComboBoxColumn
    Dim column As New DataGridViewComboBoxColumn()

    With column
        .DataPropertyName = ColumnName.TitleOfCourtesy.ToString()
        .HeaderText = ColumnName.TitleOfCourtesy.ToString()
        .DropDownWidth = 160
        .Width = 90
        .MaxDropDownItems = 3
        .FlatStyle = FlatStyle.Flat
    End With
    Return column
End Function

Private Sub SetAlternateChoicesUsingDataSource( _
    ByVal comboboxColumn As DataGridViewComboBoxColumn)
    With comboboxColumn
        .DataSource = RetrieveAlternativeTitles()
        .ValueMember = ColumnName.TitleOfCourtesy.ToString()
        .DisplayMember = .ValueMember
    End With
End Sub

Private Function RetrieveAlternativeTitles() As DataTable
    Return Populate( _
        "SELECT distinct TitleOfCourtesy FROM Employees")
End Function

Private connectionString As String = _
        "Integrated Security=SSPI;Persist Security Info=False;" _
        & "Initial Catalog=Northwind;Data Source=localhost"

Private Function Populate(ByVal sqlCommand As String) As DataTable
    Dim northwindConnection As New SqlConnection(connectionString)
    northwindConnection.Open()

    Dim command As New SqlCommand(sqlCommand, _
        northwindConnection)
    Dim adapter As New SqlDataAdapter()
    adapter.SelectCommand = command
    Dim table As New DataTable()
    table.Locale = System.Globalization.CultureInfo.InvariantCulture
    adapter.Fill(table)

    Return table
End Function

' Using an enum provides some abstraction between column index
' and column name along with compile time checking, and gives
' a handy place to store the column names.
Enum ColumnName
    EmployeeId
    LastName
    FirstName
    Title
    TitleOfCourtesy
    BirthDate
    HireDate
    Address
    City
    Region
    PostalCode
    Country
    HomePhone
    Extension
    Photo
    Notes
    ReportsTo
    PhotoPath
    OutOfOffice
End Enum

Keterangan

Properti DataSource atau Items menentukan tempat untuk mengambil data pilihan yang diperlihatkan dalam daftar drop-down kotak kombo. Saat menggunakan DataSource properti , jika data harus digambar dari properti atau kolom nondefault, maka DisplayMember properti harus diatur ke nama properti atau kolom nondefault.

DataSource Jika properti diatur ke array string, maka ValueMember dan DisplayMember tidak perlu diatur karena setiap string dalam array akan digunakan untuk nilai dan tampilan.

Mendapatkan atau mengatur properti ini mendapatkan atau mengatur DataSource properti objek yang dikembalikan oleh CellTemplate properti . Mengatur properti ini juga mengatur DataSource properti setiap sel di kolom dan me-refresh tampilan kolom. Untuk mengambil alih nilai yang ditentukan untuk sel individual, atur nilai sel setelah Anda mengatur nilai kolom.

Lihat juga

• DataGridView
• CellTemplate
• DataGridViewComboBoxCell
• DataSource
• Items
• ValueMember
• DisplayMember