//ismail Kocacan
unit uValidation;

interface

uses

   SysUtils, Variants, Classes, DB,RegularExpressions;

type
  TFieldValidatorHelper=class Helper for TField

  public

      function IsMailFormat:Boolean;
      function IsIPFormat:Boolean;
      function IsURLFormat:Boolean;

  end;

implementation

{ TFieldValidatorHelper }

function TFieldValidatorHelper.IsIPFormat: Boolean;
begin
  Result:=TRegEx.Create('(([0-9]){1,3}.){1,3}[0-9]{1,3}').IsMatch(Trim(Text));
end;

function TFieldValidatorHelper.IsMailFormat: Boolean;
begin
  Result:=TRegEx.Create('^([\w\.-]{1,64}@[\w\.-]{1,252}\.\w{2,4})$').IsMatch(Trim(Text));
end;

function TFieldValidatorHelper.IsURLFormat: Boolean;
begin
  Result:=TRegEx.Create('^(https?)://[^\s/$.?#].[^\s]*$').IsMatch(Trim(Text));
end;

end.

uValidation unit’ini projenize dahil edittikden sonra;
TQuery nesnesinin BeforePost event’inde aşağıdaki gibi bir doğrulama yapabilirsiniz.

unit uMain;
.
.
.

implementation

 uses uValidation;

procedure TfrmMain.TBL_UserBeforePost(DataSet: TDataSet);
begin
  if not DataSet.FieldByName('EMAIL').IsMailFormat then
   begin
     raise Exception.Create('Geçersiz Mail Formatı');
     Abort;
   end;

  if not DataSet.FieldByName('IP').IsIPFormat then
   begin
     raise Exception.Create('Geçersiz IP Formatı');
         Abort;
      end;
end;