[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(0, new ListItem(String.Empty, String.Empty));   control.SelectedIndex = 0;

  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"; }
 }
}