Question

Delphi中变量出错问题

代码如下：
var
dt1,dt2:TDatetime;

procedure TForm1.Button1Click(Sender: TObject);
begin
d1:=strtodatetime(Edit1.Text);
d2:=strtodatetime(Edit2.Text);
ADOQuery1.Close;
ADOQuery1.SQL.Clear;
ADOQuery1.SQL.Add('select ele from records where ele is not null and dtime between '''+d1+''' and '''+d2+'''');
ADOQuery1.Open;
end;

出错:类型不一致。
该怎么该呢？

Answer 1

between '''+d1+''' and '''+d2+''''
sql语句就是string
所以你上面不用转。
去掉d1:=strtodatetime(Edit1.Text);
d2:=strtodatetime(Edit2.Text); 2句

Answer 2

between '''+d1+''' and '''+d2+''''

between :a and :b
ADOQueryGot.Parameters.ParamValues['a'] := d1;
ADOQueryGot.Parameters.ParamValues['b'] := d2;