C#2005自己制作控件疑难

Question

你是怎么声明的？把代码贴出来看看

Answer 1

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;namespace ipBox
{    public partial class ipBox : System.Windows.Forms.TextBox
    {
        public ipBox()
        {
            InitializeComponent();
        }
        private int digitPos = 0;
        private int DelimitNumber = 0;
        private void ipBox_KeyPress(object sender, KeyPressEventArgs e)
        {
            ipBox sd = (ipBox)sender;
            sd.MaskIpAddr(e);
        }
        private void MastIpAddr(KeyPressEventArgs e)
        {
        int len = this.Text.Length;
        int indx = this.Text.LastIndexOf(".");
        if(this.SelectedText==this.Text)
        {
        indx=-1;
        digitPos=0;
        DelimitNumber=0;                            
        }
        if(Char.IsDigit(e.KeyChar)||e.KeyChar=='.'||e.KeyChar==8)
        {
        string tmp=this.Text;
        if(e.KeyChar!=8)
        {
        if(e.KeyChar!='.')
        {
        if(indx>0)
        digitPos=len-indx;
        else 
        digitPos++;
        }
        if(digitPos==3&&e.KeyChar!='.')
        {
        string tmp2=this.Text.Substring(indx+1)+e.KeyChar;
        if(Int32.Parse(tmp2)>255)//check validation
        MessageBox.Show("The number can't be bigger than 255->"+tmp2);
        else
        {
        if(DelimitNumber<3)
        {
        this.AppendText(e.KeyChar.ToString());
        this.AppendText(".");
        DelimitNumber++;
        e.Handled=true;
        }
        }
        }
        else if(digitPos==4 && DelimitNumber<3)
        this.AppendText(".");
        }
        else
        {
        e.Handled=false;
        if((len-indx)==1)
        {
        DelimitNumber--;
        if(indx>-1)
        {
         digitPos=len-indx;
        }
        else
        digitPos--;
         }
        else
        {
        if(indx>-1)
        digitPos=len-indx-1;
        }
        }
        }
        else
        e.Handled = true;
    }
    }
}
这就是我写的代码?帮忙看看