IsLetter: {是否是个字母; 范围 A..Z 与 a..z}
IsUpper: {是否是个大写字母; 范围 A..Z}
IsLower: {是否是个小写字母; 范围 a..z}
IsDigit: {是否是个十进制数字; 范围 0..9}
IsNumber: {是否是个数字符号; 范围包括 0..9, 还有 ASCII 码中的 178、179、185、188、189、190 等}
测试代码:
unit Unit1;
interface
uses
Windows, Messages,
SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs,
StdCtrls;
type
TForm1 =
class(TForm)
Button1: TButton;
Button2: TButton;
Button3: TButton;
Button4: TButton;
Button5: TButton;
procedure
Button1Click(Sender: TObject);
procedure
Button2Click(Sender: TObject);
procedure
Button3Click(Sender: TObject);
procedure
Button4Click(Sender: TObject);
procedure
Button5Click(Sender: TObject);
end;
var
Form1:
TForm1;
implementation
{$R *.dfm}
uses Character;
{IsLetter:
是否是个字母}
procedure TForm1.Button1Click(Sender:
TObject);
var
b1,b2,b3:
Boolean;
begin
b1 :=
IsLetter('A'); {是}
b2 :=
IsLetter('a'); {是}
b3 :=
IsLetter('9'); {否}
ShowMessageFmt('%s,%s,%s',
[BoolToStr(b1,True),BoolToStr(b2,True),BoolToStr(b3,True)]);
{True,True,False}
b1 :=
IsLetter('D2009', 1);
b2 :=
IsLetter('D2009', 2);
ShowMessageFmt('%s,%s',
[BoolToStr(b1,True),BoolToStr(b2,True)]);
{True,False}
end;
{IsUpper:
是否是个大写字母}
procedure TForm1.Button2Click(Sender:
TObject);
var
b1,b2,b3:
Boolean;
begin
b1 :=
IsUpper('A'); {是}
b2 :=
IsUpper('a'); {否}
b3 :=
IsUpper('9'); {否}
ShowMessageFmt('%s,%s,%s',
[BoolToStr(b1,True),BoolToStr(b2,True),BoolToStr(b3,True)]);
{True,False,False}
b1 :=
IsUpper('Delphi', 1);
b2 :=
IsUpper('Delphi', 2);
ShowMessageFmt('%s,%s',
[BoolToStr(b1,True),BoolToStr(b2,True)]);
{True,False}
end;
{IsLower:
是否是个小写字母}
procedure TForm1.Button3Click(Sender:
TObject);
var
b1,b2,b3:
Boolean;
begin
b1 :=
IsLower('A'); {否}
b2 :=
IsLower('a'); {是}
b3 :=
IsLower('9'); {否}
ShowMessageFmt('%s,%s,%s',
[BoolToStr(b1,True),BoolToStr(b2,True),BoolToStr(b3,True)]);
{False,True,False}
b1 :=
IsLower('Delphi', 1);
b2 :=
IsLower('Delphi', 2);
ShowMessageFmt('%s,%s',
[BoolToStr(b1,True),BoolToStr(b2,True)]);
{False,True}
end;
{IsDigit:
是否是个十进制数字}
procedure TForm1.Button4Click(Sender:
TObject);
var
b1,b2,b3:
Boolean;
begin
b1 :=
IsDigit('A'); {否}
b2 :=
IsDigit('½'); {否}
b3 :=
IsDigit('9'); {是}
ShowMessageFmt('%s,%s,%s',
[BoolToStr(b1,True),BoolToStr(b2,True),BoolToStr(b3,True)]);
{False,False,True}
b1 :=
IsDigit('D2009', 1);
b2 :=
IsDigit('D2009', 2);
ShowMessageFmt('%s,%s',
[BoolToStr(b1,True),BoolToStr(b2,True)]);
{False,True}
end;
{IsNumber:
是否是个数字符号}
procedure TForm1.Button5Click(Sender:
TObject);
var
b1,b2,b3:
Boolean;
begin
b1 :=
IsNumber('A'); {是}
b2 :=
IsNumber('½'); {是}
b3 :=
IsNumber('9'); {否}
ShowMessageFmt('%s,%s,%s',
[BoolToStr(b1,True),BoolToStr(b2,True),BoolToStr(b3,True)]);
{False,True,True}
b1 :=
IsNumber('123¹²³¼½¾', 1);
b2 :=
IsNumber('123¹²³¼½¾', 4); {这里的
9 个字符全都复合}
ShowMessageFmt('%s,%s',
[BoolToStr(b1,True),BoolToStr(b2,True)]);
{True,True}
end;
end.