prindb01.pas

特别方便的工具程序

unit PRINDB01;

interface

uses
  PRINTERS, Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, Grids, DBGrids, Db, DBTables;

type
  TPrintTBForm = class(TForm)
    DataSource1: TDataSource;
    Table1: TTable;
    DBGrid1: TDBGrid;
    Button1: TButton;
    Button2: TButton;
    procedure Button2Click(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  PrintTBForm: TPrintTBForm;

implementation

{$R *.DFM}

procedure TPrintTBForm.Button2Click(Sender: TObject);
const
  LeftBlank = 1; //定义页边距，单位厘米
  RightBlank = 1;
  TopBlank = 1;
  BottomBlank = 1;
var
  PointX, PointY: integer;
  PointScale, PrintStep: integer;
  s: string;
  x, y: integer;
  i: integer;
begin //获取当前打印机的分辨率
  PointX := Trunc(GetDeviceCaps(Printer.Handle, LOGPIXELSX) / 2.54);
  PointY := Trunc(GetDeviceCaps(Printer.Handle, LOGPIXELSY) / 2.54);

//根据打印机和屏幕的分辨率计算出从屏幕转换到打印机的比例
  PointScale := Trunc(GetDeviceCaps(Printer.Handle, LOGPIXELSX) / Screen.PixelsPerInch + 0.5); //横向打印
  printer.Orientation := poLandscape;
  printer.Orientation := poPortrait;
//打印的字体和大小
  printer.Canvas.Font.Name := '宋体';
  printer.canvas.Font.Size := 10;

 //根据字体的大小确定每行的高度
  s := '漳州市刑警支队';
  PrintStep := printer.canvas.TextHeight(s) + 16;

 //打印的起点位置
  x := PointX * LeftBlank;
  y := PointY * TopBlank;

 //DataSource1是DBGrid1所连接的数据源

  if ((DataSource1.DataSet).Active = true) and ((DataSource1.DataSet).RecordCount > 0) then
  begin
    printer.BeginDoc;
    (DataSource1.DataSet).First;
    while not (DataSource1.DataSet).Eof do
    begin //打印DBGrid中的所有列
      for i := 0 to DBGrid1.FieldCount - 1 do
      begin
            //假如所要打印的列超出了打印范围，则忽略该列
        if (x + DBGrid1.Columns.Items[i].Width * PointScale) <= (Printer.PageWidth - PointX * RightBlank) then
        begin //画表格线
                   //每页的第一行打印表头
          Printer.Canvas.Rectangle(x, y, x + DBGrid1.Columns.Items[i].Width * PointScale, y + PrintStep);
          if y = PointY * TopBlank then
            Printer.Canvas.TextOut(x + 8, y + 8, DBGrid1.Columns[i].Title.Caption)
          else
            Printer.Canvas.TextOut(x + 8, y + 8, DBGrid1.Fields[i].asString);
        end; //计算下一列的横坐标

        x := x + DBGrid1.Columns.Items[i].Width * PointScale;
      end;

      if not (y = PointY * TopBlank) then
        (DataSource1.DataSet).next;

      x := PointX * LeftBlank;
      y := y + PrintStep; //换页
      if (y + PrintStep) > (Printer.PageHeight - PointY * BottomBlank) then
      begin
        Printer.NewPage;
        y := PointY * TopBlank;
      end;
    end;
    printer.EndDoc;
    DataSource1.DataSet.First;
    ShowMessage('打印完成');
  end;
end;

procedure TPrintTBForm.Button1Click(Sender: TObject);
begin
  close;
end;

end.