這是個很簡單的組件，編寫它的目的也很單純，就是想解決數據錄入時的特殊字符檢查問題。一開始要寫函數實現，不過覺得麻煩，後來就想到寫一個簡單的VCL來遍歷Form上所有的組件的方法。這個VCL目前只是檢查所有的TEdit和TComboBox組件，有興趣的朋友可以自己擴充功能。
我想這個VCL對於編寫數據庫程序的人員來說還是有一點幫助的，比如對單引號的Check。
想要檢查什麼符號只要在屬性中設置一下就搞定，而且運行時只需要執行一個Checking函數，他就會自動檢查咯。
它的另一個作用就是可以作為編寫VCL的簡單入門例程。
unit SymbolChecker;
interface
uses
Windows, Messages, SysUtils, Classes, Controls,StdCtrls,Dialogs,StrUtils;
type
TCheckControl = (cTEdit, cTComboBox);
TCheckControls = set of TCheckControl;
TSymbolChecker = class(TComponent)
private
{ Private declarations }
FActive: boolean;
FCheckControls:TCheckControls;
FCheckString:String;
procedure SetActive(Value: boolean);
procedure SetCheckControls(Value: TCheckControls);
procedure SetCheckString(Value: String);
protected
{ Protected declarations }
public
{ Public declarations }
constructor Create(AOwner: TComponent); override;
published
{ Published declarations }
procedure Checking();
property Active: boolean read FActive write SetActive default false;
property CheckControls: TCheckControls read FCheckControls write SetCheckControls default [cTEdit, cTComboBox];
property CheckString: String read FCheckString write SetCheckString;
end;
procedure Register;
implementation
procedure Register;
begin
RegisterComponents(MyVCL, [TSymbolChecker]);
end;
constructor TSymbolChecker.Create(AOwner: TComponent);
begin
inherited Create(AOwner);
CheckControls := [cTEdit, cTComboBox];
end;
{ Set property Active Value }
procedure TSymbolChecker.SetActive(Value: boolean);
begin
if Value = FActive then exit;
FActive := Value;
end;
{ Set property CheckControls Value }
procedure TSymbolChecker.SetCheckControls(Value: TCheckControls);
begin
if Value = FCheckControls then exit;
FCheckControls := Value;
end;
{ Set property CheckString Value }
procedure TSymbolChecker.SetCheckString(Value: String);
begin
if Value = FCheckString then exit;
FCheckString := Value;
if Trim(FCheckString) = then SetActive(false);
end;
procedure TSymbolChecker.Checking();
var
I,J:integer;
begin
{ property Active=true then execute }
if FActive then
begin
{ property CheckTEdit=true then execute }
for I:= 0 to owner.ComponentCount - 1 do
begin
{ Check TEdit }
if (owner.Components[I] is TEdit) and (cTEdit in CheckControls) then
begin
for J :=1 to Length(Trim(FCheckString)) do
begin
if pos(MidStr(Trim(FCheckString),J,1),TEdit(owner.Components[I]).Text)>0 then
begin
ShowMessage(error symbol!);
TEdit(owner.Components[I]).SetFocus;
exit;
end;
end;
end;
{ Check TComboBox }
if (owner.Components[I] is TComboBox) and (cTComboBox in CheckControls) then
begin
for J :=1 to Length(Trim(FCheckString)) do
begin
if pos(MidStr(Trim(FCheckString),J,1),TComboBox(owner.Components[I]).Text)>0 then
begin
ShowMessage(error symbol!);
TComboBox(owner.Components[I]).SetFocus;
exit;
end;
end;
end;
end;
end;
end;
end.
最後要說明一點的是它是用Delphi6寫的。
：）
