C#自定义IP输入框控件

using System; 
using System.Collections.Generic; 
using System.ComponentModel; 
using System.Data; 
using System.Drawing; 
using System.Linq; 
using System.Text; 
using System.Windows.Forms; 
 
namespace IP 
{ 
  public delegate void FallBackEvent(IpInputBox box, int flag); 
 
  public partial class Dialog : Form 
  { 
    public Dialog() 
    { 
      InitializeComponent(); 
    } 
 
    private void Form1_Load(object sender, EventArgs e) 
    { 
      this.Controls.Add(ipBox); 
      ipBox.Location = new Point(10,10); 
    } 
 
    private IpInputBox ipBox = new IpInputBox(false); 
  } 
} 

using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
using System.Windows.Forms; 
using System.Drawing; 
 
namespace IP 
{ 
  public class IpInputBox :TextBox 
  { 
    private bool _isNetmask = false; 
    public bool IsNetmask 
    { 
      get { return _isNetmask; } 
      set { _isNetmask = value; } 
    } 
    public IpInputBox(bool isNetmask) 
    { 
      _isNetmask = isNetmask; 
 
      this.Size = new System.Drawing.Size(150, 25); 
 
      _dotLabel1.Text = "."; 
      _dotLabel2.Text = "."; 
      _dotLabel3.Text = "."; 
 
      _dotLabel1.Size = new System.Drawing.Size(10, 25); 
      _dotLabel2.Size = new System.Drawing.Size(10, 25); 
      _dotLabel3.Size = new System.Drawing.Size(10, 25); 
 
      _box1.IsNetmask = _isNetmask; 
      _box2.IsNetmask = _isNetmask; 
      _box3.IsNetmask = _isNetmask; 
      _box4.IsNetmask = _isNetmask; 
 
      _box1.Flag = 1; 
      _box2.Flag = 2; 
      _box3.Flag = 3; 
      _box4.Flag = 4; 
 
 
      this.Controls.Add(_box1); 
      this.Controls.Add(_dotLabel1); 
 
 
      this.Controls.Add(_box2); 
      this.Controls.Add(_dotLabel2); 
 
 
      this.Controls.Add(_box3); 
      this.Controls.Add(_dotLabel3); 
 
      this.Controls.Add(_box4); 
 
      this.Font = new System.Drawing.Font(this.Font.Name, 11); 
      _box1.Location = new System.Drawing.Point(-1, 2); 
      _dotLabel1.Location = new System.Drawing.Point(29, 2); 
      _box2.Location = new System.Drawing.Point(39, 2); 
      _dotLabel2.Location = new System.Drawing.Point(69, 2); 
      _box3.Location = new System.Drawing.Point(79, 2); 
      _dotLabel3.Location = new System.Drawing.Point(109, 2); 
      _box4.Location = new System.Drawing.Point(119, 2); 
 
      _box1.Box = this; 
      _box2.Box = this; 
      _box3.Box = this; 
      _box4.Box = this; 
    } 
    public void FallBackEventFun(IpInputBox box, int flag) 
    { 
      switch (flag) 
      { 
        case 1: 
          _box1.Focus(); 
          break; 
        case 2: 
          _box1.Focus(); 
          break; 
        case 3: 
          _box2.Focus(); ; 
          break; 
        case 4: 
          _box3.Focus(); ; 
          break; 
      } 
    } 
 
    private string _ipAddress = string.Empty; 
    public void UpDateIpaddress() 
    { 
      try 
      { 
        string[] sArray = ipAddress.Split(new char[] { '.' }); 
        _box1.Text = sArray[0]; 
        _box2.Text = sArray[1]; 
        _box3.Text = sArray[2]; 
        _box4.Text = sArray[3]; 
      } 
      catch (Exception exp) 
      { 
        MessageBox.Show("更新字符串失败:" + exp.Message); 
      } 
    } 
 
    /// <summary> 
    /// 获取ip地址 
    /// </summary> 
    public string IpAddressString 
    { 
      get 
      { 
        string _ipStr1 = _box1.Text; 
        string _ipStr2 = _box2.Text; 
        string _ipStr3 = _box3.Text; 
        string _ipStr4 = _box4.Text; 
        string _ipDotStr = "."; 
        _ipAddress = _ipStr1 + _ipDotStr + _ipStr2 + _ipDotStr + _ipStr3 + _ipDotStr + _ipStr4; 
        return _ipAddress; 
      } 
      set 
      { 
        _ipAddress = value; 
      } 
    } 
    private string ipAddress = string.Empty; 
 
    public string IpAddress 
    { 
      get { return ipAddress; } 
      set { ipAddress = value; } 
    } 
 
    private SubIpInputBox _box1 = new SubIpInputBox(""); 
    private SubIpInputBox _box2 = new SubIpInputBox(""); 
    private SubIpInputBox _box3 = new SubIpInputBox(""); 
    private SubIpInputBox _box4 = new SubIpInputBox(""); 
 
    private Label _dotLabel1 = new Label(); 
    private Label _dotLabel2 = new Label(); 
    private Label _dotLabel3 = new Label(); 
 
  } 
} 

using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
using System.Drawing; 
using System.Windows.Forms; 
 
namespace IP 
{ 
  public class SubIpInputBox:TextBox 
  { 
      /// <summary> 
      /// 判断是否是子网掩码,false表示ip地址,true表示子网掩码 
      /// </summary> 
      private bool _isNetmask = false; 
      private bool _isSendKey = false; 
      private System.ComponentModel.IContainer components; 
      private int _flag = 0; 
 
      public int Flag 
      { 
        get { return _flag; } 
        set { _flag = value; } 
      } 
 
      /// <summary> 
      ///  
      /// </summary> 
      public event FallBackEvent TextFallBackEvent; 
 
 
      //定义事件函数 
      public void FallBackEventFun(int flag) 
      { 
        if (TextFallBackEvent != null) 
        { 
          TextFallBackEvent(box, this.Flag); 
        } 
      } 
 
      public bool IsNetmask 
      { 
        get { return _isNetmask; } 
        set { _isNetmask = value; } 
      } 
 
      /// <summary> 
      /// 构造函数 
      /// </summary> 
      public SubIpInputBox(bool isNetmask) 
      { 
        _isNetmask = isNetmask; 
        box = new IpInputBox(_isNetmask); 
        this.Font = new System.Drawing.Font(this.Font.Name, 11); 
        this.BorderStyle = System.Windows.Forms.BorderStyle.None;//去掉边框 
        this.TextAlign = HorizontalAlignment.Center;//字体居中 
        this.Size = new System.Drawing.Size(30, 25); 
        this.MaxLength = 3; 
      } 
 
      public SubIpInputBox(string str) 
      { 
        this.Text = str; 
        this.Size = new System.Drawing.Size(30, 25); 
        this.MaxLength = 3; 
        this.BorderStyle = System.Windows.Forms.BorderStyle.None;//去掉边框 
        this.TextAlign = HorizontalAlignment.Center;//字体居中 
      } 
 
      private IpInputBox box; 
      public IpInputBox Box 
      { 
        get { return box; } 
        set { box = value; } 
      } 
 
      protected override void OnKeyUp(KeyEventArgs e) 
      { 
        base.OnKeyUp(e); 
 
 
        if (this.Text == "") 
        { 
          if (e.KeyCode.ToString() == "Back") 
          { 
            this.TextFallBackEvent += new FallBackEvent(box.FallBackEventFun); 
            this.FallBackEventFun(this.Flag); 
          } 
        } 
      } 
      protected override void OnKeyPress(KeyPressEventArgs e) 
      { 
        base.OnKeyPress(e); 
 
        //阻止从键盘输入键 
        e.Handled = true; 
 
 
        if ((e.KeyChar >= '0' && e.KeyChar <= '9') || (e.KeyChar == (char)8)) 
        { 
 
          if ((e.KeyChar == (char)8)) 
          { 
            e.Handled = false; return; 
          } 
          else 
          { 
            int len = this.Text.Length; 
            if (len < 4) 
            { 
              if (len == 0 && e.KeyChar != '0') 
              { 
                e.Handled = false; return; 
              } 
              else if (len == 0) 
              { 
                if (this.Flag == 1 && this.IsNetmask == false) 
                { 
                  return; 
                } 
              } 
              e.Handled = false; return; 
            } 
            else 
            { 
              // MessageBox.Show("编号最多只能输入3位数字！"); 
            } 
          } 
        } 
        else if (e.KeyChar == '.') 
        { 
          //MessageBox.Show("编号只能输入数字！"); 
          if (this.Text.Length != 0) 
          { 
            // 如果输入 . 就执行 TAB 键  
            SendKeys.SendWait("{TAB}"); 
          } 
        } 
        else if (this._isSendKey) 
        { 
          this.SelectAll(); 
        } 
 
      } 
 
 
      protected override void OnTextChanged(EventArgs e) 
      { 
 
        try 
        { 
          string currentStr = this.Text; 
          int currentNumber = Convert.ToInt32(currentStr); 
          this.Text = currentNumber.ToString(); 
          this.SelectionStart = currentStr.Length;//设置光标在末尾 
          if (_isNetmask == false)//表示ip地址 
          { 
 
            if (currentNumber > 223 || (currentNumber == 0 && this.Flag == 1)) 
            { 
              MessageBox.Show("你输入的" + currentStr + "不是有效数值，请指定一个介于1到223之间的数值!", "错误", MessageBoxButtons.OK, MessageBoxIcon.Warning); 
 
              if (this.Flag == 1 && currentNumber == 0) 
              { 
                this.Text = "1"; 
              } 
              else 
              { 
                this.Text = "223"; 
              } 
              _isSendKey = true; 
              this.Focus(); 
              this.SelectionStart = currentStr.Length;//设置光标在末尾 
              this.SelectAll(); 
            } 
            else 
            { 
              if (currentStr.Length == 3 && _isSendKey == false) 
              {// 当输入的字符个数为3时，跳入另外一个输入框 
                //MessageBox.Show("输入完毕"); 
                if (currentNumber == 0) 
                { 
                  this.Text = ""; 
                  MessageBox.Show("000"); 
                } 
                SendKeys.SendWait("{TAB}"); 
              } 
            } 
 
          } 
          else//子网掩码 
          { 
            if (currentNumber > 255) 
            { 
              MessageBox.Show("你输入的" + currentStr + "不是有效数值，请指定一个介于0到255之间的数值!", "错误", MessageBoxButtons.OK, MessageBoxIcon.Warning); 
              this.Text = "255"; 
              this.Focus(); 
              this.SelectionStart = currentStr.Length;//设置光标在末尾 
              this.SelectAll(); 
            } 
            else 
            { 
              if (currentStr.Length == 3 && _isSendKey == false) 
              {// 当输入的字符个数为3时，跳入另外一个输入框 
                //MessageBox.Show("输入完毕"); 
                SendKeys.SendWait("{TAB}"); 
 
              } 
            } 
          } 
        } 
        catch 
        { 
          // 异常处理 
        } 
      } 
 
      private void InitializeComponent() 
      { 
        this.SuspendLayout(); 
        //  
        // SubIpInputBox 
        //  
        this.TabIndexChanged += new System.EventHandler(this.SubTextBox_TabIndexChanged); 
        this.ResumeLayout(false); 
      } 
      private void SubTextBox_TabIndexChanged(object sender, EventArgs e) 
      { 
 
      } 
  } 
}