各位大侠！小弟做了个三层结构的查询！在客户端写入查询的sql语句及查询条件，但查询时出现“enterprisename is of unknow type" (enterp

Question

我现在的三层程序中，客户段是一个查询界面，界面的上部是几个checkbox和几个edit空间，他们一一对应，他们也是查询的检索点，比如说客户选中了第一个checkbox1（按名字查询），那edit1中的内容就是检索条件，那这样的话是不是可以这样写程序：先定义sql语句，sql:='select enterprisename（字段一）,enterpriseid（字段二） from basicinfo(表）‘，然后写：
if checkbox1.checked=true then
   edit1.enabled:=true;
   str:=str+'and enterprsiename=‘+''''+edit1.text+''''';
~~~~~~~~
~~~~
   datamodule1.clientdataset.close;
   datamodule1.clientdataset.commandtext;=sql;
   datamodule1.clientdataset.open;
   datamodule1.clientdataset.active:=true;
  with dbgrid do 
    begin~~~~~~~~
运行后，点击checkbox1（按名称查询也就是按enterprisename查询），在其后的edit中输入数据，点击查询按纽，出现（enterprisename is  of an unknow type )错误！请哪位高手赐教！！！急！

Answer 1

完整的请看：
procedure TSEnterInfoFrm.QBCEnterpriseNameClick(Sender: TObject);
begin
     if QBCEnterprisename.Checked =true then
        QBEnterprisename.Enabled:=true
        else
        QBEnterprisename.Enabled :=false;
        QBEnterprisename.Text :='';end;procedure TSEnterInfoFrm.QBCEnterpriseKindClick(Sender: TObject);
begin
     if QBCEnterprisekind.Checked =true then
        QBEnterprisekind.Enabled :=true
      else
         QBEnterprisekind.Enabled :=false;
         QBEnterprisekind.Text :='';
end;procedure TSEnterInfoFrm.QBCEnterpriseClassClick(Sender: TObject);
begin
     if QBCEnterpriseclass.Checked =true then
        QBEnterpriseclass.Enabled :=true
     else
        QBEnterpriseclass.Enabled :=true;
        QBenterpriseclass.Text :='';
end;procedure TSEnterInfoFrm.QBCEntrolMoneyClick(Sender: TObject);
begin
            if QBCEntrolmoney.Checked=true then
            begin
            QBEnrolmoneybegin.Enabled:=true;
            QBEnrolmoneyend.Enabled :=true;
            end
            else
             begin
             QBEnrolmoneybegin.Text :='';
            QBEnrolmoneyend.Text :='';
             QBEnrolmoneybegin.Enabled :=false;
            QBEnrolmoneyend.Enabled :=false;
             end;end;procedure TSEnterInfoFrm.QBCHoldDateClick(Sender: TObject);
begin
          if QBCHolddate.Checked =true then
           begin
           QBHolddatebegin.Enabled :=true;
           QBHolddateend.Enabled :=true;
           end
           else
           begin
           QBHolddatebegin.Text :='';
           QBHolddateend.Text :='';
           QBHolddatebegin.Enabled :=false;
           QBHolddateend.Enabled :=false;
           end;end;procedure TSEnterInfoFrm.QBCGovernorClick(Sender: TObject);
begin
    if QBCGovernor.Checked =true then
       QBGovernor.Enabled :=true
    else
       QBGovernor.Enabled :=false;
       QBGovernor.Text :='';
end;procedure TSEnterInfoFrm.TotalEnterpriseInfoClick(Sender: TObject);
var str:string;
    str1:string;
    str2:string;
    str3:string;
    str4:string;
    str5:string;
    str6:string;
params:array[1..8]of string;
begin
  str:='select a.enterpriseid, a.enterprisename, a.enroladdress,a.holddate,b.entrolmoney,a.economy,b.enterpriseclass,c.linkman,c.ltelephone,d.class,d.name from "basicinfo" a,"correlation" b, "contact" c,"personinfo" d';
  str:=str+' where a.enterpriseid=b.enterpriseid and a.enterpriseid=c.enterpriseid and a.enterpriseid=d.enterpriseid ';
  if QBCEnterprisename.Checked =true then
      begin
     str1:='and enterprisename='+''''+enterprisename+'''';
     str:=str+str1;
      end
      else
      begin
      str1:='';
      end;
  if QBCEnterprisekind.Checked =true then
     begin
     str2:='and enterprisekind='+''''+QBenterprisekind+'''';
     str:=str+str2;
     end
     else
     begin
     str2:='';
     end;
  if  QBCEnterpriseclass.Checked =true then
     begin
     str3:='and enterpriseclass='+''''+QBenterpriseclass.text+'''';
      str:=str+str3;
      end
     else
     begin
     str3:='';
      end;
  if  QBCEntrolmoney.Checked =true then
      begin
       str4:=' and Entrolmoney between'+ '''+QBEntrolmoneybegin.text+''''+' and'+'''' +QBentrolmoneyend.text+'''';
        str:=str+str4;
       end
       else
       begin
       str4:='';
       end;
 if QBCHolddate.Checked =true then
     begin
      str5:=' and holddate between'+''''+QBHolddatebegin.text+''''+'and'+ ''''+QBHolddateend.text+'''';
       str:=str+str5;
      end
     else
     begin
     str5:='';
     end;
  if QBCGovernor.Checked =true then
     begin
      str6:='and governor='+''''+QBgovernor.text+'''';
      str:=str+str6;
       end
       else
       begin
       str6:='';
       end;datamodule1.SBasicDataSet.Close ;
datamodule1.SBasicDataSet.CommandText :=str;
datamodule1.Sbasicdataset.open;
datamodule1.SBasicDataSet.Active:=true;
with EInfogrid do
    begin
    columns[0].fieldname:='enterpriseid';
    columns[1].fieldname:='enterprisename';
    columns[2].fieldname:='enroladdress';
    columns[3].fieldname:='holddate';
    columns[4].fieldname:='enrolmoney';
    columns[5].fieldname:='economy';
    columns[6].fieldname:='enterprisekind';
    columns[7].fieldname:='linkman';
    columns[8].fieldname:='ltelephone';
    columns[9].FieldName:='name';
    end;end;
end.