其中 ITInfoID = + DropDownList1.SelectedValue +"

where ITInfoID =" + DropDownList1.SelectedValue + "", conn); ds = new DataSet(); da.Fill(ds); GridView1.DataSource = ds.Tables[0]; GridView1.DataBind(); }

您需要另一个双引号字符:

You need another double quote character:

da = new SqlDataAdapter(select * from ITInfo

" span> + DropDownList1.SelectedValue +" ，conn) ;

where ITInfoID =" + DropDownList1.SelectedValue + "", conn);

成为

da = new SqlDataAdapter("select * from ITInfo