delphi显示 jpg、png、gif 图片及 gif 动画的方法

本文介绍了一种使用Delphi实现不同格式图片加载与显示的方法,包括常见的JPEG、PNG及GIF图片,并演示了如何通过按钮点击事件来切换并显示这些图片。此外,还展示了如何在Delphi中播放GIF动画。

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ExtCtrls;

type
TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure Button4Click(Sender: TObject);
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

uses jpeg, GIFImg, pngimage;

{显示 jpg 图片}
procedure TForm1.Button1Click(Sender: TObject);
var
jpg: TJPEGImage;
begin
jpg := TJPEGImage.Create;
jpg.LoadFromFile('C:/Temp/Test.jpg');
Canvas.Draw(0, 0, jpg);
jpg.Free;
end;

{显示 png 图片}
procedure TForm1.Button2Click(Sender: TObject);
var
png: TPngImage;
begin
png := TPngImage.Create;
png.LoadFromFile('C:/Temp/Test.png');
Canvas.Draw(0, 0, png);
png.Free;
end;

{显示 gif 图片}
procedure TForm1.Button3Click(Sender: TObject);
var
gif: TGIFImage;
begin
gif := TGIFImage.Create;
gif.LoadFromFile('C:/Temp/Test.gif');
Canvas.Draw(0, 0, gif);
gif.Free;
end;

{显示 gif 动画}
procedure TForm1.Button4Click(Sender: TObject);
var
gif: TGIFImage;
begin
gif := TGIFImage.Create;
gif.LoadFromFile('C:/Temp/Test.gif');
gif.Animate := True;

with TImage.Create(Self) do begin
    Parent := Self;
    Left := 0;
    Top := 0;
    Picture.Assign(gif);
end;

gif.Free;
end;

end.

procedure BitmapFileToPNG(const Source, Dest: String); var Bitmap: TBitmap; PNG: TPNGObject; begin Bitmap := TBitmap.Create; PNG := TPNGObject.Create; {In case something goes wrong, free booth Bitmap and PNG} try Bitmap.LoadFromFile(Source); PNG.Assign(Bitmap); //Convert data into png PNG.SaveToFile(Dest); finally Bitmap.Free; PNG.Free; end end; Converting from PNG file to Windows bitmap file The above inverse. Loads a png and saves into a bitmap procedure PNGFileToBitmap(const Source, Dest: String); var Bitmap: TBitmap; PNG: TPNGObject; begin PNG := TPNGObject.Create; Bitmap := TBitmap.Create; {In case something goes wrong, free booth PNG and Bitmap} try PNG.LoadFromFile(Source); Bitmap.Assign(PNG); //Convert data into bitmap Bitmap.SaveToFile(Dest); finally PNG.Free; Bitmap.Free; end end; Converting from TImage to PNG file This method converts from TImage to PNG. It has full exception handling and allows converting from file formats other than TBitmap (since they allow assigning to a TBitmap) procedure TImageToPNG(Source: TImage; const Dest: String); var PNG: TPNGObject; BMP: TBitmap; begin PNG := TPNGObject.Create; {In case something goes wrong, free PNG} try //If the TImage contains a TBitmap, just assign from it if Source.Picture.Graphic is TBitmap then PNG.Assign(TBitmap(Source.Picture.Graphic)) //Convert bitmap data into png else begin //Otherwise try to assign first to a TBimap BMP := TBitmap.Create; try BMP.Assign(Source.Picture.Graphic); PNG.Assign(BMP); finally BMP.Free; end; end; //Save to PNG format PNG.SaveToFile(Dest); finally PNG.Free; end end;
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值