calctax.pas

工资管理系统的代码实例

unit CalcTax;

interface

uses
  DB, GZGLCommon, ADODB;
                       
type
  TCalcTax = class (TObject)
  private
    procedure GetSl(AJsjs: Double; var ASl, ASskcs: Double);
  public
    procedure CalcSj(var AGZRec: TGZRec);
  end;
implementation

{ TCalcTax }

procedure TCalcTax.CalcSj(var AGZRec: TGZRec);
var
  l_Jsjs, l_Qzd, l_Sl, l_Sskcs: Double;
begin
  with TAdoQuery.Create(nil) do
  try
    Connection := AdoGzgl;
    SQL.Text := 'Select * from Qzd';
    Open;
    if RecordCount <> 0  then
      l_Qzd := FieldByName('Qzd').AsFloat
    else
      l_Qzd := 0;
    Close;
  finally
    Free;
  end;

  // 计算税金
  with AGZRec do
  begin
    l_Jsjs := Jbgz + Zwgz + Bt + Kq - l_Qzd;
    GetSl(l_Jsjs, l_Sl, l_Sskcs);
    Sj := l_Jsjs * l_Sl - l_Sskcs;
  end;
end;

procedure TCalcTax.GetSl(AJsjs: Double; var ASl, ASskcs: Double);
begin
  with TAdoQuery.Create(nil) do
  try
    Connection := AdoGzgl;
    SQL.Text := 'Select * from Slxx Order by Sxe';
    Open;

    // 找到匹配的税率和速算扣除数
    First;
    while not eof do
    begin
      if AJsjs > FieldByName('Sxe').AsFloat then
        Next
      else begin
        ASl := FieldByName('Sl').AsFloat;
        ASskcs := FieldByName('Sskcs').AsFloat;
        Break;
      end;
    end;

    if Eof then
    begin
      Last;
      ASl := FieldByName('Sl').AsFloat;
      ASskcs := FieldByName('Sskcs').AsFloat;
    end;
    Close;
  finally
    Free;
  end;
end;

end.