ComboBox With Error Provider in C#.net

ComboBox With Error Provider in C#.net


Create CustomError Provider in your project

 using System.Collections.Generic;  
 using System.Windows.Forms;  
 namespace naraayananProject.UserControl  
 {  
   public class CustomErrorProvider :ErrorProvider   
   {  
     public List<Control> GetControls()  
     {  
       return this.GetControls(this.ContainerControl);  
     }  
     public List<Control> GetControls(Control ParentControl)  
     {  
       List<Control> ret = new List<Control>();  
       if (!string.IsNullOrEmpty(this.GetError(ParentControl)))  
         ret.Add(ParentControl);  
       foreach (Control c in ParentControl.Controls)  
       {  
         List<Control> child = GetControls(c);  
         if (child.Count > 0)  
           ret.AddRange(child);  
       }  
       return ret;  
     }  
   }  
 }  

Declare Custom Error Provider in your Current Class:

 public static CustomErrorProvider ErrProvider = new CustomErrorProvider();  

  public static bool ComboBoxErrorControl(ComboBox cmb, string message, TabPage tp)  
     {  
       if (!String.IsNullOrEmpty(cmb.Text))  
       {  
         ErrProvider.SetError(cmb, "");  
       }  
       else  
       {  
         ErrProvider.SetError(cmb, message);  
       }  
       object[] control = ErrProvider.GetControls(tp).ToArray();  
       if (control.Length > 0)  
         return false;  
       else  
         return true;  
     }