Delphi TRichEdit.Perform(EM_FORMATRANGE,0,Longint(@fmtRange));
我想找到需要Delphi TRichEdit.Perform(EM_FORMATRANGE,0,Longint(@fmtRange));,delphi,trichedit,Delphi,Trichedit,我想找到需要TRichEdit控件在不显示垂直滚动条的情况下渲染自身的高度。 我使用这个代码 function RichEditHeight(var RE : TRichEdit; aForm : TForm) : integer; var fmtRange: TFormatRange; begin FillChar(fmtRange, SizeOf(fmtRange), 0); with fmtRange do begin hDC := aForm.canvas
TRichEdit
控件在不显示垂直滚动条的情况下渲染自身的高度。
我使用这个代码
function RichEditHeight(var RE : TRichEdit; aForm : TForm) : integer;
var fmtRange: TFormatRange;
begin
FillChar(fmtRange, SizeOf(fmtRange), 0);
with fmtRange do begin
hDC := aForm.canvas.Handle;
hdcTarget := hDC;
rc.left := 0;
rc.right := (RE.ClientWidth * 1440) div screen.pixelsPerInch;
rc.top := 0;
rc.Bottom := MaxInt;
rcPage := rc;
chrg.cpMin := 0;
chrg.cpMax := -1;
end;
RE.Perform(EM_FORMATRANGE, 0, Longint(@fmtRange));
result := round(fmtRange.rc.Bottom*screen.pixelsPerInch/1440);
RE.Perform(EM_FORMATRANGE, 0, 0);
end;
当文档只有几页时(最后,解决方案非常简单!
TRichedit有一个事件onResizerRequest,其中控件的实际高度由rect参数给出。我不明白这个问题。你说的“执行代码”是什么意思?在这个代码中:RE.perform
(EM_FORMATRANGE,0,Longint(@fmtRange));很可能有限制,而不是“执行”但是控件的。使用您指定的消息和参数执行控件的窗口过程-模拟SendMessage而不发送,仅此而已。在任何显示器上,如果没有滚动条,您无法显示15页A4页面,为什么要在意呢?我使用滚动框来实现此目的。如果高度足以容纳所有页面,我可以使用scrollbox的滚动条没有欺骗它的sOk。如果你想让任何人通过复制问题来查看,请提供一个。
unit Unit32;
interface
uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Vcl.ComCtrls, winAPI.richedit, JvExStdCtrls, JvRichEdit, Vcl.ExtCtrls;
type
TForm32 = class(TForm)
ScrollBox1: TScrollBox;
Button1: TButton;
RichEdit1: TJvRichEdit;
panel1: TPanel;
OpenDialog1: TOpenDialog;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var Form32: TForm32;
implementation
{$R *.dfm}
function RichEditHeight(var RE : TjvRichEdit; aForm : TForm) : integer;
var fmtRange: TFormatRange;
begin
FillChar(fmtRange, SizeOf(fmtRange), 0);
with fmtRange do begin
hDC := aForm.canvas.Handle;
hdcTarget := hDC;
rc.left := 0;
rc.right := (RE.ClientWidth * 1440) div screen.pixelsPerInch;
rc.top := 0;
rc.Bottom := 500000;
rcPage := rc;
chrg.cpMin := 0;
chrg.cpMax := -1;
end;
RE.Perform(EM_FORMATRANGE, 0, Longint(@fmtRange));
result := round(fmtRange.rc.Bottom*screen.pixelsPerInch/1440);
RE.Perform(EM_FORMATRANGE, 0, 0);
end;
procedure TForm32.Button1Click(Sender: TObject);
begin
with OpenDialog1 do
if execute then begin
RichEdit1.lines.LoadFromFile(filename);
panel1.height := RichEditHeight(RichEdit1,Form32);
end;
end;
end.
object Form32: TForm32
Left = 0
Top = 0
Caption = 'Form32'
ClientHeight = 615
ClientWidth = 874
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'Tahoma'
Font.Style = []
OldCreateOrder = False
PixelsPerInch = 96
TextHeight = 13
object ScrollBox1: TScrollBox
Left = 0
Top = 0
Width = 874
Height = 615
Align = alClient
TabOrder = 0
ExplicitWidth = 885
ExplicitHeight = 583
object Button1: TButton
Left = 632
Top = 24
Width = 75
Height = 25
Caption = 'Button1'
TabOrder = 0
OnClick = Button1Click
end
object panel1: TPanel
Left = 0
Top = 0
Width = 457
Height = 561
Caption = 'panel1'
TabOrder = 1
object RichEdit1: TJvRichEdit
Left = 1
Top = 1
Width = 455
Height = 559
Align = alClient
Font.Charset = GREEK_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'Tahoma'
Font.Style = []
ParentFont = False
ScrollBars = ssVertical
SelText = ''
TabOrder = 0
ExplicitHeight = 279
end
end
end
object OpenDialog1: TOpenDialog
Left = 656
Top = 88
end
end