这个是查询的:procedure TTbooksearch.BitBtn5Click(Sender: TObject); begin if edit2.Text ='' then begin adodataset1.Close ; showmessage('请输入书名!'); abort; end; with adocommand1 do begin commandtype:=cmdtext; commandtext:='select * from book where 书名 =:name '; parameters.ParamByName('name').Value :=edit2.Text ; adodataset1.Recordset :=execute; edit2.Text :=''; end; if adodataset1.RecordCount =0 then begin showmessage('无此书!') ; adodataset1.Close; end else adodataset1.Open; end;删除: procedure TTdelreader.BitBtn1Click(Sender: TObject); var loc:boolean; loc1:boolean; begin adotable1.Open ; adotable2.Open ; if edit1.Text ='' then begin showmessage('输入要删除的学号!'); abort; end; loc1:=adotable1.Locate('学生编号',edit1.Text ,[]) ; loc := adotable2.Locate('学生编号',edit1.Text ,[]); if loc=false then begin edit1.Text :=''; showmessage('没有这个学号!'); abort; end else begin if loc1 then begin showmessage('该学生还有借书记录,不能删除!'); abort; end else begin showmessage('确实要删除这个学生!'); adotable2.Locate('学生编号',edit1.Text ,[]); adotable2.Delete ; showmessage('删除完毕!'); end; end ; end; 增加: with adotable1 do begin open; insert; fields.fieldbyname('图书编号').asstring:=edit1.text; fields.fieldbyname('书名').asstring:=edit2.text; fields.fieldbyname('作者').asstring:=edit3.text; fields.fieldbyname('剩余数量').asstring:=edit4.text; fields.fieldbyname('价格/元').asstring:=edit6.text; fields.fieldbyname('出版日期').asstring:=maskedit1.text; fields.fieldbyname('出版社').asstring :=edit5.Text; post; end;
begin
if edit2.Text ='' then
begin
adodataset1.Close ;
showmessage('请输入书名!');
abort;
end;
with adocommand1 do
begin
commandtype:=cmdtext;
commandtext:='select * from book where 书名 =:name ';
parameters.ParamByName('name').Value :=edit2.Text ;
adodataset1.Recordset :=execute;
edit2.Text :='';
end;
if adodataset1.RecordCount =0 then
begin
showmessage('无此书!') ;
adodataset1.Close;
end
else
adodataset1.Open;
end;删除:
procedure TTdelreader.BitBtn1Click(Sender: TObject);
var
loc:boolean;
loc1:boolean;
begin
adotable1.Open ;
adotable2.Open ;
if edit1.Text ='' then
begin
showmessage('输入要删除的学号!');
abort;
end;
loc1:=adotable1.Locate('学生编号',edit1.Text ,[]) ;
loc := adotable2.Locate('学生编号',edit1.Text ,[]);
if loc=false then
begin
edit1.Text :='';
showmessage('没有这个学号!');
abort;
end
else
begin
if loc1 then
begin
showmessage('该学生还有借书记录,不能删除!');
abort;
end
else
begin
showmessage('确实要删除这个学生!');
adotable2.Locate('学生编号',edit1.Text ,[]);
adotable2.Delete ;
showmessage('删除完毕!');
end;
end ;
end;
增加:
with adotable1 do
begin
open;
insert;
fields.fieldbyname('图书编号').asstring:=edit1.text;
fields.fieldbyname('书名').asstring:=edit2.text;
fields.fieldbyname('作者').asstring:=edit3.text;
fields.fieldbyname('剩余数量').asstring:=edit4.text;
fields.fieldbyname('价格/元').asstring:=edit6.text;
fields.fieldbyname('出版日期').asstring:=maskedit1.text;
fields.fieldbyname('出版社').asstring :=edit5.Text;
post;
end;
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