DataGridView的數據綁定單元格

Question

我有一個 function 數據綁定作為參數傳遞的DataGridViewRow的單元格之一。

public static void DataBindCells(DataGridViewRow row)
{
    DataGridViewComboBoxCell priceModes = row.Cells["ColumnPriceMode"] as DataGridViewComboBoxCell;
    priceModes.DataSource = UtilityClass.GetDataTable("SELECT PriceModeID,PriceModeName FROM PriceModes");
    priceModes.DisplayMember = "PriceModeName";
    priceModes.ValueMember = "PriceModeID";
}

此 function 的使用：有一個“添加行”按鈕調用DataBindCells function。 使用這個 function 的DataGridView實際上是用來填寫發票的。 行的列是：ItemName、PriceMode、Price、Quantity、Amount。

價格模式為 Piece/kg/Dozen 等。當用戶想要在賬單中添加項目時，單擊 Add Row 按鈕。

問題是當上面的 function 執行時，在DataGridViewComboBoxCell中沒有選擇任何內容。 有什么方法可以默認選擇第一個項目。

Answer 1

下面的例子證明 DefaultValuesNeeded 可以做你想做的事。

...

命名空間 WindowsFormsApplication1 {

public static class Helper {
    public static DataTable ToDataTable<T>(this List<T> list) where T : class {
        Type type = typeof ( T );
        var ps = type.GetProperties ( );
        var cols = from p in ps
                   select new DataColumn ( p.Name , p.PropertyType );

        DataTable dt = new DataTable ( );
        dt.Columns.AddRange ( cols.ToArray ( ) );

        list.ForEach ( (l) => {
            List<object> objs = new List<object> ( );
            objs.AddRange ( ps.Select ( p => p.GetValue ( l , null ) ) );
            dt.Rows.Add ( objs.ToArray ( ) );
        } );

        return dt;
    }
}

public enum SendTypes {
    WeiBo ,
    QQ ,
    MSN ,
    EML
}

public class Receiver {
    public string Address {
        get;
        set;
    }
    public SendTypes SendType {
        get;
        set;
    }
    public string Msg {
        get;
        set;
    }
}

public partial class Form1 : Form {
    public Form1() {
        InitializeComponent ( );
    }

    private void SetDataGrid() {
        DataGridViewComboBoxColumn colSendType = new DataGridViewComboBoxColumn ( );
        colSendType.Items.AddRange ( SendTypes.EML, SendTypes.MSN, SendTypes.QQ, SendTypes.WeiBo );
        colSendType.Name = "SendType";

        colSendType.DataPropertyName = "SendType";
        this.dataGridView1.Columns.Add ( colSendType );

        DataGridViewTextBoxColumn colAddress = new DataGridViewTextBoxColumn ( );
        colAddress.Name = "Address";
        colAddress.DataPropertyName = "Address";
        this.dataGridView1.Columns.Add ( colAddress );

        this.dataGridView1.AutoGenerateColumns = false;
        //this.dataGridView1.AllowUserToAddRows = true;
    }

    private void LoadData() {
        var tmp = new Receiver {
            Address = "http://www.weibo.com/?uid=1000",
            SendType = SendTypes.WeiBo,
            Msg = "Test"
        };
        List<Receiver> datas = new List<Receiver>();
        datas.Add(new Receiver {
            Address = "http://www.weibo.com/?uid=1000",
            SendType = SendTypes.WeiBo,
            Msg = "Test"
        });
        datas.Add(new Receiver(){
            Address = "10001",
            SendType = SendTypes.QQ,
            Msg = "test"
        });
        datas.Add(new Receiver(){
            Address = "xling@abc.com",
            SendType = SendTypes.EML,
            Msg = "TEST TEST"
        });

        this.dataGridView1.DataSource = datas;//.ToDataTable();
    }

    private void Form1_Load(object sender , EventArgs e) {
        this.SetDataGrid ( );
        this.LoadData ( );
    }

    private void dataGridView1_DefaultValuesNeeded(object sender , DataGridViewRowEventArgs e) {
        dataGridView1.Rows[e.Row.Index].Cells["SendType"].Value = SendTypes.EML;
    }
}

}

Answer 2

DefaultValuesNeeded

單元格[2] 是 DataGridViewComboBoxColumn

    private void dataGridView1_DefaultValuesNeeded(object sender , DataGridViewRowEventArgs e) {
        dataGridView1.Rows[e.Row.Index].Cells[2].Value = "EML";
    }

Answer 3

在完全綁定 GridView 后添加選擇標准（您要選擇哪一行）。 一旦你控制並開始動態綁定，自動魔法的東西就會飛出 window。

你想在這里完成什么？ 我想有一種更簡單的方法可以做到這一點，它更符合標准綁定 model 和事件。