[Umbraco] Data Type之Render control

继续探讨Data Type。如果你创建过Data Type，你就会知道创建一个新的Data Type都需要指定一个Render control，这有点类似开始C#时用到的继承。

那么如何创建我们自己的Render control呢？

其实也很简单，将前一篇的demo略加改造就可以了

 public class ConnectionStringDataType : AbstractDataEditor
 {
  [DataEditorSetting("Connectionstring")]
  public String ConnectionString { get; set; }

  [DataEditorSetting("Select statement")]
  public string SelectStatement { get; set; }

  [DataEditorSetting("Text column")]
  public string TextColumn { get; set; }

  [DataEditorSetting("Value column")]
  public string ValueColumn { get; set; }

  private DropDownList control = new DropDownList();

  public ConnectionStringDataType()
  {
   base.RenderControl = control;
   control.Init += new EventHandler(control_Init);
   base.DataEditorControl.OnSave += new AbstractDataEditorControl.SaveEventHandler(DataEditorControl_OnSave);
  }

  void DataEditorControl_OnSave(EventArgs e)
  {
   base.Data.Value = control.SelectedValue;
  }

  void control_Init(object sender, EventArgs e)
  {
   control.DataSource = Microsoft.ApplicationBlocks.Data.SqlHelper.ExecuteReader(ConnectionString, CommandType.Text, SelectStatement);
   control.DataTextField = TextColumn;
   control.DataValueField = ValueColumn;
   control.DataBind();
   control.Items.Insert(, new ListItem(String.Empty, String.Empty));   control.SelectedIndex = ;

   if (base.Data.Value != null)
    control.SelectedValue = base.Data.Value.ToString();
  }

  public override Guid Id
  {
   get { return new Guid("FEDBD0B7-F318-4F1A-8D37-97C3B7DCB5D8"); }
  }

  public override string DataTypeName
  {
   get { return "Db driven dropdown"; }
  }
 }