檢查輸入是否爲空並提示

•  Drag the ValidationModule item from toolbox  to the Designer's Required Modules section.

  [DefaultClassOptions]
  [System.ComponentModel.DefaultProperty("Title")]
  public class Position : BaseObject {
     //...
     private string title;
     [RuleRequiredField(DefaultContexts.Save)]
     public string Title {
        get { return title; }
        set { SetPropertyValue("Title", ref title, value); }
     }
  }