我需要确定创建的表中是否有条目。
我需要的是,

if (TableIsEmpty) then
     do_something
else
     do_something_else;

我写这篇文章的目的是:
Function IsTableEmpty:Boolean;
Var
  DataSource : string;
Begin
  DataSource :=
     'Provider=Microsoft.Jet.OLEDB.4.0'+
     ';Data Source=c:\mydb.mdb'+
     ';Persist Security Info=False';

  Form2.ADOConnection1.ConnectionString := DataSource;
  Form2.ADOConnection1.LoginPrompt := False;
  Form2.ADOCommand1.Connection := Form2.ADOConnection1;
  Form2.ADOTable1.ConnectionString := DataSource;
  Form2.ADOTable1.Connection := Form2.ADOConnection1;
  if (Form2.ADOTable1.IsEmpty)then
      result := true
  else
      result := false;
End;

但是不管表的状态如何,这个函数都返回true!
编辑***
修改代码:
Function IsTableEmpty:Boolean;
Var
  DataSource, cs : string;
Begin
  DataSource :=
     'Provider=Microsoft.Jet.OLEDB.4.0'+
     ';Data Source=c:\Users.mdb'+
     ';Persist Security Info=False';

  Form2.ADOConnection1.ConnectionString := DataSource;
  Form2.ADOConnection1.LoginPrompt := False;
  Form2.ADOCommand1.Connection := Form2.ADOConnection1;
  Form2.ADOTable1.Connection := Form2.ADOConnection1;
  Form2.ADOTable1.TableName := 'userIdentification';
  Form2.ADOTable1.Active := True;
  cs := 'Select * from userIdentification';
  Form2.ADOCommand1.CommandText := cs;
  Form2.ADOCommand1.Execute;
  if Form2.ADOTable1.RecordCount <= 0 then
     result := true
  else
     result := false;
  Form2.ADOConnection1.Close;
End;

此函数始终返回false!啊!

最佳答案

if Form2.ADOTable1.RecordCount =< 0 then
     do_something
else
     do_something_else;

在成功执行select语句后运行

10-05 22:42
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