Introduction
This example source code shows you how to
ask the GrowthChart control to export a
JPG image with a given size.
Note!
This is not a standard feature of the
component, and may not be available in
your version.
|
| Source code example,
Delphi |
procedure TMyApplication.BtnExportJpgClick(Sender: TObject);
//Export a JPG image of the graph
Var
myFileName : String;
myWidth, myHeight : integer;
myLineDrawStyle : integer;
begin
myFileName := 'c:\temp\chart.jpg';
myWidth := 210;
myHeight := 297;
myLineDrawStyle := 0;
//0=ldsDefault, 1=ldsDotted or 2=ldsDithered
GrowthChart.ExportAsJPEG(myFileName, myWidth, myHeight, myLineDrawStyle);
end; |
| Source code example,
Visual Basic |
Private Sub CommandButton1_Click()
XUSGraph1.ExportAsJPEG "c:\temp\usgraph.jpeg", 210, 297,ldsDithered
End Sub
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|
Note!
In order to maintain a good print result of the gray lines used in the background
three options are provided. These options are
normally available in the lower left corner of the Print
dialog, but when you call the ExportAsJpeg method you must specify
which type of line drawing emulation you
would like to use.
|
| ldsDefault |
Gray colors are printed as gray and the printer will do it's own conversion. This mode means that the
light gray lines are sometimes translated into dotted lines of different widths. In some cases the lines may even disappear completely. The
light gray lines may even come out as solid black. HP printers are particularly difficult with this option set to Default. |
| ldsDithered |
With this option set the growth chart
component will do the translation of light gray into a B&W pattern which looks like
light gray. The advantage of this mode over the Dotted is that the background appears somewhat lighter. |
| ldsDotted |
With this option set light gray lines will be printed using equally sized dots, approximately 0.5 mm long. This is the mode used by the original paper growth charts provided by Socialstyrelsen. |
Display in an HTML page
If you wish to display the JPG image in
an HTML page it is important to generate
a JPG file which corresponds to the size
in which you would like to display the
image. If you do not respect this rule
your browser will resize the image and
the result may not be accurate.For display on screen a width of 550
pixels may be appropriate.
If you want to print the image and come
as close as possible to the original
quality of the growth chart you will
need to specify a much larger image. An
image size such as 2100 x 2970 pixels
generates an image of acceptable quality
for A4 printouts.
Generate the image and present it in an
HTML page similar to the example below:
<html>
<body>
<img border="0"
src="c:\temp\chart.jpg"
align="left"
width="770"
height="1100">
</body>
</html>
In order to obtain an image of maximum
size you will have to adapt the margins
set in your browser.
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