18th issue (May 17): Computer and life
Half-year version: Computer and life
Half-year column: Programming skills
Publishing date: 19990517
Produce Chinese statement with Delphi
China Space Technology Research Institute of Maternity
In database application development, an important issue for system designers and programmakers need to consider how to design and output reports, we can pick in Delphi
Use multiple programs to solve this problem. If you use OLE automation technology to output data to MS-Word, MS-Excel, but most direct, most local or use
QuickReport report components in Delphi3.0 / 40. It is Norwegian Qusoft specializes in Delphi, using QuickReport to quickly design in the West
Reports for people habits.
However, when designing a Chinese statement, the author found that the vertical line and slash between the columns and columns in QuickReport; although QuickReport provided
Tqshape control, use this control to draw vertical lines between columns, but if the user does not correctly adjust the height of the Tqshape instance, the vertical line in the output report is not
Continuous is long, and if we adjust the height of a BAN, we will have to adjust the height of all Tqshape instances under this band; as for the slash,
The QuickReport report component does not provide this feature.
The author carefully found relevant information, successfully solved the above problems, hoping to help everyone.
Solutions
To create a new control with TQShape, the new control can draw vertical lines, slash and backlash.
The PAINT method of the TQShape class is overloaded, so that it can be very intuitive in the design phase. Users can select the type of line in the design phase,
If you select a straight line, the control automatically adjusts its height to the height of the BAND, the user can adjust its lateral position but cannot adjust its height; if you choose the slash, the user can
Adjust the length and tilt of the slash as needed.
The Print method of the TQShape class is overloaded, which can output a straight line and the slash at the run phase.
Description: This control can only draw straight and slashes. If the reader needs to draw a rectangle and circle, you can use the TQShape control to be implemented.
Control design steps
Step 1. Use the control wizards provided by Delphi, select Tqshape as the parent class, create a new class TMYQRSHAPE, and select the appropriate package (package), and finally generate unit files.
Step 2. In the generated unit file, add an enumerated type.
TLINES = (None, Topbottom, Bottomtop); None, TopBottom, Bottomtop, three types of values, representing straight, slash / and antilactors /.
Step 3. Increase the private member flinetype: tLINEs in the new class TMYQRShape, add the publication property LINETYPE: TLINES Read
FLINETYPE WRITE SETFLINETYPE.
Step 4. Establish a process setFLINETYPE.
Procedure
TMYQRSHAPE.SETFLINETYPE (Value: TLINES);
Begin
IF value <> flinetype kil
Begin
FLINETYPE: = Value;
INVALIDATE;
END;
END;
Step 5. Overload the Paint method.
Procedure TMYQRSHAPE.PAINT;
Begin
Case LineType of
Bottomtop:
Begin
Canvas.Moveto (0, Height);
Canvas.LineTo (Width, 0);
END;
Topbottom:
Begin
Canvas.Moveto (0, 0);
Canvas.LineTo (Width, Height);
END;
None:
Begin
Height: = parent.height;
TOP: = 0;
Width: = 4;
Shape: = QRSVERTLINE
Inherited paint;
END;
END;
END;
Step 6. Overload the Print method.
Procedure TmyQRShape.print (OFSX, OFSY: Integer); Begin
With qrprinter do
Begin
Case LineType of
Bottomtop:
Begin
Canvas.Moveto (XPOS (OFSX Size.Left), YPOS (OFSY SIZE.TOP) Height;
Canvas.LineTo (XPOSX Size.left) Width, Ypos (OFSY SIZE.TOP);
END;
Topbottom:
Begin
Canvas.Moveto (XPOSX Size.Left), YPOS (OFSY SIZE.TOP);
Canvas.Lineto (XPOSX Size.Left) Width, Ypos (OFSY SIZE.TOP) Height);
END;
None:
Inherited Print (OFSX, OFSY);
END;
END;
END;
Step 7. Save and install the TMYQRSHAPE control.
This control is debugged, installs, and successfully applied to the development of a database management system under Delphi40. The full code of the control is as follows:
Source program:
Unit myqrshape;
Interface
Uses
Windows, Messages, Sysutils, Classes, Graphics,
Controls, Forms, Dialogs,
Quickrpt, qrctrls;
Type
TLINES = (None, TopBottom, Bottomtop);
TMYQRSHAPE = Class (TQRShape)
Private
FlineType: TLINES;
Procedure setflinetype (value: tlines);
protected
Procedure Print (OFSX, OFSY: Integer; OVERRIDE;
proca;
public
Published
Property LineType: Tlines Read FlineType Write SetFLINETYPE
END;
PROCEDURE register;
IMPLEMentation
Procedure
TMYQRSHAPE.SETFLINETYPE (Value: TLINES);
Begin
IF value <> flinetype kil
Begin
FLINETYPE: = Value;
INVALIDATE;
END;
END;
Procedure TMYQRSHAPE.PAINT;
Begin
Case LineType of
Bottomtop:
Begin
Canvas.Moveto (0, Height);
Canvas.LineTo (Width, 0);
END;
Topbottom:
Begin
Canvas.Moveto (0, 0);
Canvas.LineTo (Width, Height);
END;
None:
Begin
Height: = parent.height;
TOP: = 0;
Width: = 4;
Shape: = QRSVERTLINE
Inherited paint;
END;
END;
END;
Procedure TmyQRShape.print (OFSX, OFSY: Integer);
Begin
With qrprinter do
Begin
Case LineType of
Bottomtop:
Begin
Canvas.Moveto (xpos (OFSX Size.Left), YPOS (OFSY SIZE.TOP) Height); Canvas.LineTo (XPOS (OFSX Size.LEFT) Width, Ypos (OFSY SIZE.TOP));
END;
Topbottom:
Begin
Canvas.Moveto (XPOSX Size.Left), YPOS (OFSY SIZE.TOP);
Canvas.Lineto (XPOSX Size.Left) Width, Ypos (OFSY SIZE.TOP) Height);
END;
None:
Inherited Print (OFSX, OFSY);
END;
END;
END;
PROCEDURE register;
Begin
Registercomponents ('QReport', [TMYQRSHAPE]);
END;
End.
