variant 类型是指在编译过程中无法确定其数据类型的变量类型,他有可能是各种数据类型
lookup具体用法:
function Lookup(const KeyFields: String; const KeyValues: Variant; const ResultFields: String): Variant;
用法如下
procedure TForm1.Button1Click(Sender: TObject);
var
V: Variant;
C: Integer;
A: String;
begin
V := Table1.Lookup('Company;State',
VarArrayOf(['Blue Sports', 'OR']),
'CustNo;Addr1');
if not (VarType(V) in [varNull]) then begin
C := V[0];
A := V[1];
ShowMessage(IntToStr(C) + #10 + A);
end
else
ShowMessage('Search unsuccessful!');
end;