只是想学习一下写IP地址控件！！！
请指教！！！

这里有一个：
http://vcl.vclxx.org/DELPHI/D32FREE/PHIPADD.ZIP

试试以下代码：
unit IPAddressEdit;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,ComCtrls, CommCtrl,
  StdCtrls;

type
  TIPAddressEdit = class(TEdit)
  private
    { Private declarations }
  protected
    procedure CreateParams(var Params: TCreateParams); override;
  public
    { Public declarations }
  published
    { Published declarations }
  end;

procedure Register;

implementation

procedure Register;
begin
  RegisterComponents('Liren.z', [TIPAddressEdit]);
end;

{ TIPAddressEdit }

procedure TIPAddressEdit.CreateParams(var Params: TCreateParams);
begin
  inherited CreateParams(Params);
  InitCommonControl(ICC_INTERNET_CLASSES);
  CreateSubClass(Params, WC_IPADDRESS);
end;

end.

D6中已经有了一个TIPAddress//IP地址组件

这样只是调用windows本身的ip地址控件吧？？
我想要一个具体实现的！！！
只是出于学习的目的

这是一个完整的源代码：
unit CXIPAddress;
interface
uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs
  ,commctrl,comctrls;

type
  TFieldRange = record
    LowRange: Byte;
    HighRange: Byte;
  end;
  TphFieldChange = procedure(Sender: TObject; Field: Integer;
                  Value: Integer) of object;
  TCXIPAddress = class(TWinControl)
  private
    { Private declarations }
    FActiveField:Byte;
    FCreating: Boolean;
    FValue: LongInt;
    FFieldRanges: array [0..3] of TFieldRange;
    FOnChange: TNotifyEvent;
    FOnEnter: TNotifyEvent;
    FOnExit: TNotifyEvent;
    FOnFieldChange: TphFieldChange;
    FFirstIPAddress: Byte;
    FSecondIPAddress: Byte;
    FThirdIPAddress: Byte;
    FFourthIPAddress: Byte;
    procedure SetActiveField(Value:Byte);
    function GetFirstIPAddress: Byte;
    procedure SetFirstIPAddress(Value: Byte);
    function GetSecondIPAddress: Byte;
    procedure SetSecondIPAddress(Value: Byte);
    function GetThirdIPAddress: Byte;
    procedure SetThirdIPAddress(Value: Byte);
    function GetFourthIPAddress: Byte;
    procedure SetFourthIPAddress(Value: Byte);
    function GetIPAddress: LongInt;
    procedure SetIPAddress(Value:Longint);
    function GetBlank: Boolean;
    function GetFieldRanges(Field: Integer): TFieldRange;
    procedure SetFieldRanges(Field:integer; Value: TFieldRange);
    //procedure SetValue(Value: Cardinal);
    //function GetValue: LongInt;
    //procedure WMNotifyFormat(var Message: TMessage); message WM_NOTIFYFORMAT;
    procedure CNNotify(var Message: TWMNotify); message CN_NOTIFY;
    procedure CNCommand(var Message: TWMCommand); message CN_COMMAND;
    //procedure WMSetFont(var Message: TWMSetFont); message WM_SETFONT;
  protected
    { Protected declarations }
    procedure CreateParams(var Params: TCreateParams); override;
    procedure CreateWnd; override;
  public
    { Public declarations }
    constructor Create(AOwner: TComponent); override;
    procedure ClearAddress;
    function StringToIp(Value: String): Longint;
    function IPToString(Ip: Longint): string;
    procedure SetAllRanges(Range: TFieldRange);
    property IPAddress: Longint read GetIPAddress write SetIPAddress;    
  published
    property ActiveField: Byte read FActiveField write SetActiveField;
    property Blank: Boolean read GetBlank;
    property FirstRange: TFieldRange index 0 read GetFieldRanges write SetFieldRanges;
    property SecondRange: TFieldRange index 1 read GetFieldRanges write SetFieldRanges;
    property ThirdRange: TFieldRange index 2 read GetFieldRanges write SetFieldRanges;
    property FourthRange: TFieldRange index 3 read GetFieldRanges write SetFieldRanges;
    property Field0: Byte read GetFirstIPAddress write SetFirstIPAddress;
    property Field1: Byte read GetSecondIPAddress write SetSecondIPAddress;
    property Field2: Byte read GetThirdIPAddress write SetThirdIPAddress;
    property Field3: Byte read GetFourthIPAddress write SetFourthIPAddress;
    property OnChange: TNotifyEvent read FOnChange write FOnChange;
    property OnEnter: TNotifyEvent read FOnEnter write FOnEnter;
    property OnExit: TNotifyEvent read FOnExit write FOnExit;
    property OnFieldChange: TphFieldChange read FOnFieldChange write FOnFieldChange;
    property Font;
    property Enabled;
    property TabOrder;
    property TabStop;
    property ParentShowHint;
    property ShowHint;
    property Hint;
    property PopupMenu;
    property Visible;
  end;
procedure Register;
implementation
procedure Register;
begin
  RegisterComponents('CXLib', [TCXIPAddress]);
end;
procedure TCXIPAddress.ClearAddress;
begin
  Perform(IPM_CLEARADDRESS, 0, 0);
end;
procedure TCXIPAddress.CNCommand(var Message: TWMCommand);
begin
  case Message.NotifyCode of
    EN_CHANGE:
       if not FCreating then
    if Assigned(FOnChange) then FOnChange(self);
    EN_KILLFOCUS:
      if Assigned(FOnExit) then FOnExit(self);
    EN_SETFOCUS:
      if Assigned(FOnEnter) then FOnEnter(self);
  end;
end;
procedure TCXIPAddress.CNNotify(var Message: TWMNotify);
var
  IPAddress: PNMIPADDRESS;
begin
  with (Message.NMHdr)^ do
  begin
    case Code of
      IPN_FIELDCHANGED:
     begin
          IPAddress:= PNMIPADDRESS(Message.NMHdr);
          FActiveField:=IPAddress^.iField;
          case IPAddress^.iField of
            0: FFirstIPAddress := IPAddress^.iValue;
            1: FSecondIPAddress := IPAddress^.iValue;
            2: FThirdIPAddress := IPAddress^.iValue;
            3: FFourthIPAddress := IPAddress^.iValue;
          end;
          if Assigned(FOnFieldChange) then FOnFieldChange(self,
            IPAddress^.iField, IPAddress^.iValue);
     end;
    end;
  end;
end;

constructor TCXIPAddress.Create(AOwner: TComponent);
var
  i: integer;
begin
  CheckCommonControl(ICC_INTERNET_CLASSES or ICC_BAR_CLASSES);
  inherited Create(AOwner);
  For i:= 0 to 3 do
  begin
    FFieldRanges[i].LowRange:= 0;
    FFieldRanges[i].HighRange:= 255;
  end;
  FFirstIPAddress:= 0;
  FSecondIPAddress:= 0;
  FThirdIPAddress:= 0;
  FFourthIPAddress:= 0;
  FValue:= MakeIPAddress(FFirstIPAddress, FSecondIPAddress,
   FThirdIPAddress, FFourthIPAddress);
  Height:= 25;
  Width:= 151;
 TabSTop:= True;
end;
procedure TCXIPAddress.CreateParams(var Params: TCreateParams);
begin
  inherited CreateParams(Params);
  CreateSubClass(Params, WC_IPADDRESS);
end;
procedure TCXIPAddress.CreateWnd;
begin
  FCreating := True;
  try
    inherited CreateWnd;
    SetIPAddress(FValue);
  finally
    FCreating := False;
  end;
end;
function TCXIPAddress.GetBlank: Boolean;
begin
  Result:= Boolean(perform(IPM_ISBLANK, 0, 0));
end;
function TCXIPAddress.GetFieldRanges(Field: Integer): TFieldRange;
begin
  Result:= FFieldRanges[Field];
end;
function TCXIPAddress.GetFirstIPAddress: Byte;
begin
  Result:= FIRST_IPADDRESS(IPAddress);//GetIPAddress(0);
end;
function TCXIPAddress.GetFourthIPAddress: Byte;
begin
  Result:= FOURTH_IPADDRESS(IPAddress);//GetIPAddress(3);
end;
function TCXIPAddress.GetIPAddress: LongInt;
var
  buffer: LongInt;
begin
  buffer:= 0;
  perform(IPM_GETADDRESS, 0, LongInt(@Buffer));
  Result:= Buffer;
end;
function TCXIPAddress.GetSecondIPAddress: Byte;
begin
  Result:= SECOND_IPADDRESS(IPAddress);//GetIPAddress(1);
end;
function TCXIPAddress.GetThirdIPAddress: Byte;
begin
  Result:=THIRD_IPADDRESS(IPAddress); //GetIPAddress(2);
end;
procedure TCXIPAddress.SetActiveField(Value: Byte);
begin
  if FActiveField=Value then Exit;
  if ( Value < 4 ) then begin
    SendMessage(Handle, IPM_SETFOCUS, wParam(Value), 0);
    FActiveField:= Value;
  end;
end;
procedure TCXIPAddress.SetAllRanges(Range: TFieldRange);
var
  I:integer;
begin
  for i:= 0 to 3 do
  begin
    SetFieldRanges(i, Range);
  end;
end;
procedure TCXIPAddress.SetFieldRanges(Field: integer; Value: TFieldRange);
begin
  if Value.LowRange > Value.HighRange then
    exit;
  if (FFieldRanges[Field].LowRange <> Value.LowRange) or
    (FFieldRanges[Field].HighRange <> Value.HighRange) then
  begin
    FFieldRanges[Field]:= Value;
    perform(IPM_SETRANGE, Field,
      MakeIPRange(Value.LowRange, Value.HighRange));
  end;
end;
procedure TCXIPAddress.SetFirstIPAddress(Value: Byte);
begin
  if (FFirstIPAddress <> Value)  then
  begin
    FFirstIPAddress:= Value;
    IPAddress:=MAKEIPADDRESS(FFirstIPAddress, FSecondIPAddress,
       FThirdIPAddress, FFourthIPAddress);
  end;
end;
procedure TCXIPAddress.SetFourthIPAddress(Value: Byte);
begin
  if (FFourthIPAddress <> Value)  then
  begin
    FFourthIPAddress:= Value;
    IPAddress:=MAKEIPADDRESS(FFirstIPAddress, FSecondIPAddress,
       FThirdIPAddress, FFourthIPAddress);//SetIPAddress;
  end;
end;
procedure TCXIPAddress.SetIPAddress(Value:Longint);
begin
  if FValue=Value then Exit;
  Perform(IPM_SETADDRESS, 0,
     MAKEIPADDRESS(FFirstIPAddress, FSecondIPAddress,
       FThirdIPAddress, FFourthIPAddress));
  Perform(IPM_GETADDRESS, 0, Longint(@FValue));
end;
procedure TCXIPAddress.SetSecondIPAddress(Value: Byte);
begin
  if (FSecondIPAddress <> Value)  then
  begin
    FSecondIPAddress:= Value;
    IPAddress:=MAKEIPADDRESS(FFirstIPAddress, FSecondIPAddress,
       FThirdIPAddress, FFourthIPAddress);//SetIPAddress;
  end;
end;
procedure TCXIPAddress.SetThirdIPAddress(Value: Byte);
begin
  if (FThirdIPAddress <> Value)  then
  begin
    FThirdIPAddress:= Value;
    IPAddress:=MAKEIPADDRESS(FFirstIPAddress, FSecondIPAddress,
       FThirdIPAddress, FFourthIPAddress);//SetIPAddress(;
  end;
end;
function TCXIPAddress.IPToString(Ip: Longint):string;
begin
  Result:= IntToStr(First_IPAddress(Ip))+'.'+IntToStr(Second_IPAddress(Ip))+'.'+
           IntToStr(Third_IPAddress(Ip))+'.'+IntToStr(Fourth_IPAddress(Ip));
end;
function TCXIPAddress.StringToIp(Value: string):LongInt;
var B: Array[0..3] of Byte;
    Str: String;
    i, Cnt : Integer;
begin
  B[0]:= 0;
  B[1]:= 0;
  B[2]:= 0;
  B[3]:= 0;
  Cnt:= 0;
  i:= Pos('.', Value);
  while (Length(Value) > 0) and ( Cnt < 4 ) do begin
    if ( i = 0 ) then i:= Length(Value)+1;
    Str:= Copy(Value, 0, i-1);
    B[Cnt]:= StrToInt(Str);
    Value:= Copy(Value, i+1, Length(Value));
    i:= Pos('.', Value);
    Inc(Cnt);
  end;
  Result:= MakeIPAddress(b[0], b[1], b[2], b[3]);
end;
end.
//改进ipaddress变成ip,增加字符串形式的ipAddress

我说了我是想学习一下如何来写的！！
只是想看看源码,并不是使用！！！！
请高人指点了！！！

以上是一个IP地址控件源码

从TCustomEdit继承不行吗？？？
完全自己写处理的过程！！！

没有人吗？？？