テスト文字列読み込みクラス:TStringReader
3505 ワード
TStringReaderはTStringWriterの方法よりずっと少なく、それぞれ:文字、行またはすべての読み取り;
文字を読み取る際に得るのは文字符号化であり、全てまたは行毎に読み取るのは文字列であり、文字配列にも読み取ることができる.
文字を読み取る際に得るのは文字符号化であり、全てまたは行毎に読み取るのは文字列であり、文字配列にも読み取ることができる.
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;
Button6: TButton;
Button7: TButton;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
procedure Button3Click(Sender: TObject);
procedure Button4Click(Sender: TObject);
procedure Button5Click(Sender: TObject);
procedure Button6Click(Sender: TObject);
procedure Button7Click(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
// TStringReader.Read ,
procedure TForm1.Button1Click(Sender: TObject);
var
Reader: TStringReader;
i: Integer;
begin
Reader := TStringReader.Create('ABCDEFGHIJKLMNOPQRSTUVWXYZ');
{ }
i := Reader.Read;
ShowMessageFmt('%d : %s', [i, Chr(i)]); {65 : A}
{ }
i := Reader.Read;
ShowMessageFmt('%d : %s', [i, Chr(i)]); {66 : B}
{ }
i := Reader.Peek;
ShowMessageFmt('%d : %s', [i, Chr(i)]); {67 : C}
Reader.Free;
end;
//
procedure TForm1.Button2Click(Sender: TObject);
var
Reader: TStringReader;
i: Integer;
begin
Reader := TStringReader.Create(' Delphi ');
{ }
i := Reader.Read;
ShowMessageFmt('%d : %s', [i, Chr(i)]); {19975 : }
{ }
i := Reader.Read;
ShowMessageFmt('%d : %s', [i, Chr(i)]); {19968 : }
{ }
i := Reader.Peek;
ShowMessageFmt('%d : %s', [i, Chr(i)]); {30340 : }
Reader.Free;
end;
//
procedure TForm1.Button3Click(Sender: TObject);
var
Reader: TStringReader;
begin
Reader := TStringReader.Create('123' + sLineBreak + 'abc' + sLineBreak + 'xyz');
ShowMessage(Reader.ReadLine); {123}
ShowMessage(Reader.ReadLine); {abc}
ShowMessage(Reader.ReadLine); {xyz}
Reader.Free;
end;
//
procedure TForm1.Button4Click(Sender: TObject);
var
Reader: TStringReader;
begin
Reader := TStringReader.Create('123' + sLineBreak + 'abc' + sLineBreak + 'xyz');
ShowMessage(Reader.ReadToEnd); {123 / abc / xyz}
Reader.Free;
end;
//
procedure TForm1.Button5Click(Sender: TObject);
var
Reader: TStringReader;
str: string;
begin
Reader := TStringReader.Create('123' + sLineBreak + 'abc' + sLineBreak + 'xyz');
while Reader.Peek > 0 do str := str + Chr(Reader.Read);
ShowMessage(str); {123 / abc / xyz}
Reader.Free;
end;
//
procedure TForm1.Button6Click(Sender: TObject);
var
Reader: TStringReader;
str: string;
begin
Reader := TStringReader.Create('123' + sLineBreak + 'abc' + sLineBreak + 'xyz');
while Reader.Peek > 0 do str := str + Reader.ReadLine;
ShowMessage(str); {123abcxyz}
Reader.Free;
end;
//
procedure TForm1.Button7Click(Sender: TObject);
var
Reader: TStringReader;
buf: TCharArray;
begin
Reader := TStringReader.Create('ABCDEFGHIJKLMNOPQRSTUVWXYZ');
SetLength(buf, 3);
Reader.ReadBlock(buf, 0, Length(buf));
ShowMessageFmt('%s%s%s', [buf[0], buf[1], buf[2]]); {ABC}
Reader.Free;
end;
end.