ErrorProvider : ErrorProvider : GUI Windows Forms C# Examples

    
using  System;
using  System.Drawing;
using  System.Collections;
using  System.ComponentModel;
using  System.Windows.Forms;
using  System.Data;

public  class  ErrorForm  :  System.Windows.Forms.Form
{
    private  System.ComponentModel.Container  components  =  null;
    private  System.Windows.Forms.Label  label1;
    private  System.Windows.Forms.Button  btnValidate;
    private  System.Windows.Forms.ErrorProvider  errorProvider1;
    private  System.Windows.Forms.TextBox  txtInput;

    public  ErrorForm()
    {
        InitializeComponent();
    }

    protected  override  void  Dispose(  bool  disposing  )
    {
        if(  disposing  )
        {
            if  (components  !=  null)  
            {
                components.Dispose();
            }
        }
        base.Dispose(  disposing  );
    }

    private  void  InitializeComponent()
    {
        this.errorProvider1  =  new  System.Windows.Forms.ErrorProvider();
        this.label1  =  new  System.Windows.Forms.Label();
        this.txtInput  =  new  System.Windows.Forms.TextBox();
        this.btnValidate  =  new  System.Windows.Forms.Button();
        this.SuspendLayout();
        //  
        //  errorProvider1
        //  
        this.errorProvider1.BlinkRate  =  500;
        this.errorProvider1.BlinkStyle  =  System.Windows.Forms.ErrorBlinkStyle.AlwaysBlink;
        this.errorProvider1.ContainerControl  =  this;
        //  
        //  label1
        //  
        this.label1.Font  =  new  System.Drawing.Font("Arial  Black",  12F);
        this.label1.Location  =  new  System.Drawing.Point(8,  8);
        this.label1.Name  =  "label1";
        this.label1.Size  =  new  System.Drawing.Size(376,  56);
        this.label1.TabIndex  =  2;
        this.label1.Text  =  "The  following  text  box  only  allows  5  characters.    Try  to  enter  more...";
        //  
        //  txtInput
        //  
        this.txtInput.Location  =  new  System.Drawing.Point(144,  80);
        this.txtInput.Name  =  "txtInput";
        this.txtInput.Size  =  new  System.Drawing.Size(120,  20);
        this.txtInput.TabIndex  =  0;
        this.txtInput.Text  =  "";
        this.txtInput.Validating  +=  new  System.ComponentModel.CancelEventHandler(this.txtInput_Validating);
        //  
        //  btnValidate
        //  
        this.btnValidate.Location  =  new  System.Drawing.Point(16,  72);
        this.btnValidate.Name  =  "btnValidate";
        this.btnValidate.Size  =  new  System.Drawing.Size(112,  32);
        this.btnValidate.TabIndex  =  1;
        this.btnValidate.Text  =  "OK";
        //  
        //  ErrorForm
        //  
        this.AutoScaleBaseSize  =  new  System.Drawing.Size(5,  13);
        this.ClientSize  =  new  System.Drawing.Size(400,  125);
        this.Controls.Add(this.label1);
        this.Controls.Add(this.btnValidate);
        this.Controls.Add(this.txtInput);
        this.Name  =  "ErrorForm";
        this.Text  =  "Error  Trapper";
        this.ResumeLayout(false);

    }

    [STAThread]
    static  void  Main()  
    {
        Application.Run(new  ErrorForm());
    }

    private  void  txtInput_Validating(object  sender,  System.ComponentModel.CancelEventArgs  e)
    {
        //  Check  if  the  text  length  is  greater  than  5.
        if(txtInput.Text.Length  >  5)
        {
            errorProvider1.SetError(  txtInput,  "Can't  be  greater  than  5!");
        }  
        else
            errorProvider1.SetError(txtInput,  "");
    }
}