定制ObjectDataSource控件的设计视图外观

DataSource是2.0里面很重要的数据访问控件，不过DataSource类控件在设计视图总是Render成灰色的一块饼，除了ID什么信息也没有，看起不是太爽。不过现在发现了 System.Web.UI.Design.WebControls 这个namespace，“包含可用于扩展对 Web 服务器控件的设计时支持的类”。于是拿最有用的ObjectDataSource来试了试，结果可以做成这样：
[DisplayName("VeryObjectOataSource"), Description("VeryDxZ's ObjectDataSource")]
[Designer("DxZ.Common.DataBinding.VeryObjectDataSourceDesigner")]
public class VeryObjectDataSource : ObjectDataSource

public class VeryObjectDataSourceDesigner : System.Web.UI.Design.WebControls.ObjectDataSourceDesigner
public override string GetDesignTimeHtml()
VeryObjectDataSource veryODS = (VeryObjectDataSource)this.Component;
StringBuilder htmlStrBuilder = new StringBuilder();

htmlStrBuilder.Append("<div style='margin:2px; padding:2px; background-color: buttonface; color: windowtext; font: messagebox;'>");

htmlStrBuilder.AppendFormat("<strong>{0}</strong> - {1}<br/>", veryODS.GetType().Name, veryODS.ID);
if (veryODS.TypeName != null && veryODS.TypeName != string.Empty)
htmlStrBuilder.AppendFormat("TypeName={0}<br/>", veryODS.TypeName);
if (veryODS.DataObjectTypeName != null && veryODS.DataObjectTypeName != string.Empty)
htmlStrBuilder.AppendFormat("DataObject={0}<br/>", veryODS.DataObjectTypeName);

if (veryODS.SelectMethod != null && veryODS.SelectMethod != string.Empty)
htmlStrBuilder.Append("HasMethod=Select");

if (veryODS.InsertMethod != null && veryODS.InsertMethod != string.Empty)
htmlStrBuilder.Append(",Insert");
if (veryODS.UpdateMethod != null && veryODS.UpdateMethod != string.Empty)
htmlStrBuilder.Append(",Update");
if (veryODS.DeleteMethod != null && veryODS.DeleteMethod != string.Empty)
htmlStrBuilder.Append(",Delete");

htmlStrBuilder.AppendFormat("<br/>Caching={0}, Paging={1}", veryODS.EnableCaching, veryODS.EnablePaging);
}

htmlStrBuilder.Append("</div>");

return htmlStrBuilder.ToString();
}
}

注意VeryObjectDataSource类的Attribute：
[Designer("DxZ.Common.DataBinding.VeryObjectDataSourceDesigner")]。
没有这句来指明Designer的话控件不会依照自定义的去Render。源代码见这里

上面这些只是外观的定制，当然还可以在ObjectDataSource构造函数加一些初始化的参数等等，方便程序设计时使用。同时，这种定制外观的方法对Xml和Substitution等同样Render不出什么内容的控件也适用哦。