函数原型 function VarIsNull(const V: Variant): Boolean;
-----------------------------------------------------------------------------
VarAsType 将Variant转为另外一个型态的Variant.
-----------------------------------------------------------------------------
VarCast
-----------------------------------------------------------------------------
Unit System
函数原型 function VarAsType(const V: Variant; VarType: Integer):
Variant;
函数原型 procedure VarCast(var Dest: Variant; const Source: Variant;
VarType: Integer);
说明 VarType不可为varArray or varByRef.
-----------------------------------------------------------------------------
VarType 传回Variant的型态.
-----------------------------------------------------------------------------
Unit System
函数原型 function VarType(const V: Variant): Integer;
-----------------------------------------------------------------------------
VarClear 将variant清除,成为Unassigned状态.
-----------------------------------------------------------------------------
Unit System
函数原型 procedure VarClear(var V: Variant);
-----------------------------------------------------------------------------
VarCopy 拷贝一个variant.
-----------------------------------------------------------------------------
Unit System
函数原型 procedure VarCopy(var Dest: Variant; const Source: Variant);
说明 与Dest:=Source;效果一样.
-----------------------------------------------------------------------------
VarFromDateTime 将DateTime转为Variant.
-----------------------------------------------------------------------------
VarToDateTime 将Variant转为DateTime.
-----------------------------------------------------------------------------
Unit System
函数原型 function VarFromDateTime(DateTime: TDateTime): Variant;
函数原型 function VarToDateTime(const V: Variant): TDateTime;
=============================
函数
==============================
procedure TForm1.Button2Click(Sender: TObject);
var
Bitmap: TBitmap;
begin
Bitmap := TBitmap.Create;
try
Bitmap.LoadFromFile(''''G:\33.bmp '''');
Form1.Canvas.Brush.Bitmap := Bitmap;
Form1.Canvas.FillRect(Rect(0,0,18,15));
finally
Form1.Canvas.Brush.Bitmap := nil;
Bitmap.Free;
end;
end;
## Canvas, Brush, Bitmap, FillRect Example
=======================================
TextOut
=======================================
procedure TForm1.FormCreate(Sender: TObject);
var
HeaderSection: THeaderSection;
I: Integer;
begin
for I := 0 to 4 do
begin
HeaderSection := HeaderControl1.Sections.Add;
HeaderSection.Text := ''''Text Section '''' + IntToStr(I);
HeaderSection.MinWidth := length(HeaderSection.Text) * Font.Size;
// Owner draw every other section
if (I mod 2 = 0) then
HeaderSection.Style := hsOwnerDraw
else
HeaderSection.Style := hsText;
end;
end;
procedure TForm1.HeaderControl1DrawSection(HeaderControl: THeaderControl;
Section: THeaderSection; const Rect: TRect; Pressed: Boolean);
begin
with HeaderControl.Canvas do
begin
// highlight pressed sections
if Pressed then
Font.Color := clRed
else
Font.Color := clBlue;
TextOut(Rect.Left + Font.Size, Rect.Top + 2, ''''Owner Drawn text'''');
end;
end;
## HeaderSection, OnDrawSection, Sections, Canvas, TextOut example
----------------------------------------------------------
Trunc Example
-----------------------------------------------------------
procedure TForm1.Button1Click(Sender: TObject);
var
S, T: string;
begin
Str(1.4:2:1, T);
S := T + '''' Truncs to '''' + IntToStr(Trunc(1.4)) + #13#10;
Str(1.5:2:1, T);
S := S + T + '''' Truncs to '''' + IntToStr(Trunc(1.5)) + #13#10;
Str(-1.4:2:1, T);
S := S + T + '''' Truncs to '''' + IntToStr(Trunc(-1.4)) + #13#10;
Str(-1.5:2:1, T);
S := S + T + '''' Truncs to '''' + IntToStr(Trunc(-1.5));
MessageDlg(S, mtInformation, [mbOk], 0);
end;
未归类
--------------------
WrapText
--------------------
SysUtils
type TSysCharSet = set of Char
var
S, R: string;
begin
S:= ''''123456_123456_123456'''';
R:= WrapText( S, #13#10, [''''1'''', ''''4''''], 4);
MessageDlg( R, mtInformation, [mbOk], 0);
end;
================================
WideCharToStrVar(Source: PWideChar;var Dest: string );
-------------------------
System
-----------------
=========================
WideCharToString( Source: PWideChar ): string;
-------------------------
System
=============================
WideCharLenToStrVar( Source: PWideChar;SourceLen: Integer;var Dest: string );
------------------------------
System
==============================
WideCharLenToString(Source: PWideChar;SourceLen: Integer ): string
-----------------------
System
============================
AnsiCompareFileName(const S1, S2: string ): Integer; SysUtils
===================================
AnsiExtractQuotedStr (var S: PChar;Quote: Char ): string;
SysUtils
var
S1: PChar;
S2: string;
begin
S1:= ''''/??. ?????????? /???.56/'''';
S2:= AnsiExtractQuotedStr(S1,''''/''''); // S2 := ''''??. ?????????? ''''
MessageDlg(S2, mtInformation, [mbOk], 0);
end;
----------------------------------------------------------
AnsiLastChar( const S: string ): PChar;
SysUtils
----------------------------------------------------------
AnsiLowerCaseFileName( const S: string ): string;
SysUtils
----------------------------------------------------------
AnsiPos ( const Substr, S: string ): Integer
SysUtils
var
Substr, S: string;
I: Integer;
begin
S:= ''''???????? ??????'''';
Substr:= ''''???'''';
I:= AnsiPos(Substr, S); // I:= 3
...
end;
----------------------------------------------------------
AnsiQuotedStr (const S: string;Quote: Char ): string;
SysUtils
var
S: string;
begin
S:= ''''1997-1998??.'''';
S:= AnsiQuotedStr(S, ''''-''''); // S := ''''-1997--1998??.-''''
MessageDlg(S, mtInformation, [mbOk], 0);
end;
----------------------------------------------------------
AnsiSameStr ( const S1, S2: string ): Boolean;
SysUtils
----------------------------------------------------------
AnsiSameText ( const S1, S2: string ): Boolean;
SysUtils
----------------------------------------------------------
AnsiStrComp( S1, S2: PChar ): Integer
SysUtils
----------------------------------------------------------
AnsiStrIComp( S1, S2: PChar ): Integer;
SysUtils
----------------------------------------------------------
AnsiStrLastChar( P: PChar ): PChar;
SysUtils
----------------------------------------------------------
AnsiStrLComp(S1, S2: PChar;Ma << 上一页 [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] ... 下一页 >> |
