ONLINE HELP
 WINDEVWEBDEV AND WINDEV MOBILE

Help / WLanguage / WLanguage functions / Controls, pages and windows / Drawing functions
  • Displaying a PNG image
  • Transparent image in PNG format
WINDEV
WindowsLinuxUniversal Windows 10 AppJavaReports and QueriesUser code (UMC)
WEBDEV
WindowsLinuxPHPWEBDEV - Browser code
WINDEV Mobile
AndroidAndroid Widget iPhone/iPadIOS WidgetApple WatchMac CatalystUniversal Windows 10 App
Others
Stored procedures
Saves an image contained in a variable of type Image:
  • in a PNG file.
  • in memory.
Linux Caution: A specific configuration is required to use this function in Linux. For more details, see The drawings.
Example
MyImage is Image = "Test.gif"
// Saves the image found in MyImage in "C:\Documents\Image.PNG"
ResSave = Mymage.SavePNG("C:\Documents\Image.PNG")
MyImage is Image = "Test.gif"
// Saves the image contained in MyImage in memory
ResSave = MyImage.SavePNG(inMemory)
Syntax
WINDEVWEBDEV - Server codeReports and QueriesUniversal Windows 10 AppAndroidiPhone/iPadIOS WidgetMac CatalystJavaUser code (UMC)Ajax

Saving an image in a PNG file Hide the details

<Result> = <Image variable>.SavePNG(<File name> [, <Transparency color>])
<Result>: Boolean
  • True if the image was saved,
  • False otherwise. To get more details on the error, use ErrorInfo with the errMessage constant.
<Image variable>: Image variable
Name of the Image variable to be used.
<File name>: Character string
Name and full (or relative) path of PNG file. A UNC path can be used. The file extension is optional.
Caution:
  • The destination directory must exist in order for the image to be saved.
  • The existence of the PNG file is not checked. This file is automatically overwritten if it already exists.
<Transparency color>: Optional integer
Color that will be considered as being transparent in the image. This color can correspond to:If this parameter is not specified, the generated image is not transparent.
Universal Windows 10 App Syntax not available

Saving an image in memory Hide the details

<Result> = <Image variable>.SavePNG(<inMemory> [, <Transparency color>])
<Result>: Buffer
Byte string containing the image in PNG format.
Then, this byte string can be assigned to an Image control, saved in a file (fSaveText), sent via a network (with the Socket functions), ...
<Image variable>: Image variable
Name of the Image variable to be used.
<inMemory>: Constant
inMemory: Constant used to save an image in memory.
<Transparency color>: Optional integer
Color that will be considered as being transparent in the image. This color can correspond to:If this parameter is not specified, the generated image is not transparent.
Android This parameter is ignored.
Remarks

Displaying a PNG image

Caution: If the image in PNG format is semi-transparent, the display of the image is slower.

Transparent image in PNG format

To save a transparent image in PNG format, the Image control must be filled with the transparent color beforehand.
Example used to draw a transparent line and to save it in PNG format:
MyImage is Image = "Test.gif"
MyImage.StartDrawing(dWithOpacity)
MyImage.ChangeMode(drawDefault)
FOR nI = 0 _À_ MyImage..Width
FOR nJ = 0 _À_ MyImage1..Height
 MyImage.DrawPoint(nI, nJ, RGB(255,255,255), 0)
END
END
MyImage.Pen(RGB(100, 020, 200), 0,10, 100)
MyImage.DrawLine(10, 10, 100, 10)
MyImage.SavePNG(CompleteDir(fExeDir()) + "img.png")
Component: wd290pnt.dll
Minimum version required
  • Version 24
This page is also available for…
Comments
Click [Add] to post a comment

Last update: 06/21/2023

Send a report | Local help