string newsql,wheresql
if sle_1.text<>"" then
wheresql=sle_1.text
newsql="select * from t_customer where 客户编号= *:wheresql*;"
dw_1.setsqlselect(newsql)
dw_1.retrieve()
else
messagebox("提示","请输入
正确的
客户编号")
end if

语句不对

string newsql,wheresql
if sle_1.text<>"" then
wheresql=sle_1.text
newsql="select * from t_customer where 客户编号= *"+wheresql+"*"
dw_1.setsqlselect(newsql)
dw_1.settransobject(事务)
dw_1.retrieve()
else
messagebox("提示","请输入正确的客户编号")
end if