根据单价和数量计算总金额

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    Label5: TLabel;
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    Edit4: TEdit;
    Edit5: TEdit;
    Edit6: TEdit;
    Button1: TButton;
    Label6: TLabel;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

function UnivalentQuantity(Univalent,Quantity: real): real;

implementation

{$R *.dfm}

function UnivalentQuantity(Univalent,Quantity: real): real;      //单价x数量
begin
  UnivalentQuantity := Univalent * Quantity;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  Label6.Caption := '总金额：' +
  floattostr(
  UnivalentQuantity(strtofloat(Edit1.Text),strtofloat(Edit4.Text)) +
  UnivalentQuantity(strtofloat(Edit2.Text),strtofloat(Edit5.Text)) +
  UnivalentQuantity(strtofloat(Edit3.Text),strtofloat(Edit6.Text))
  )
  + '元';
end;

end.