输入框联想功能的实现

 1<TD class="dataField" align="left" width="35%"><asp:textbox id="txtProductID" runat="server" Width="180px" onkeyup="showtips()" onkeydown="enterTips()"></asp:textbox><asp:requiredfieldvalidator id="RequiredFieldValidator2" runat="server" ControlToValidate="txtProductID" ErrorMessage="必填"></asp:requiredfieldvalidator>
 2                                                    <div id="Layerb" style="Z-INDEX: 50; LEFT: 480px; VISIBILITY: hidden; WIDTH: 138px; POSITION: absolute; TOP: 250px">
 3                                                        <select id='sel' multiple onkeydown='if(event.keyCode==13)_ctl0_txtProductID.value=value,sel.style.display="none",_ctl0_txtProductID.focus()'>
 4                                                        </select>
 5                                                        <script language="javascript">
 6                                                            var sel = document.getElementById("sel");
 7                                                            var productID = document.getElementById("_ctl0_txtProductID");
 8                                                            var showProd = document.getElementById("_ctl0_txtShowProd").value.split(",");
 9                                                            function showtips()
10                                                            {
11                                                                document.all['Layerb'].style.visibility = '';
12                                                                if(sel.value!=productID.value)
13                                                                {
14                                                                    var msg = new Array();
15                                                                    msg = showProd;
16                                                                    sel.style.display='';
17                                                                    sel.length=0;
18                                                                    var len=msg.length;
19                                                                    var re=new RegExp("^"+event.srcElement.value,"i")
20                                                                    for(i=0;i<len;i++) if(re.test(msg[i])==true) sel.add(new Option(msg[i],msg[i])),sel[0].selected=true;
21                                                                }
22                                                            }
23                                                            function enterTips()
24                                                            {
25                                                                e=event.keyCode;
26                                                                if(e==13) event.srcElement.value=sel.value,sel.style.display='none';
27                                                                if(e==40) sel.focus();
28                                                            }
29                                                            document.onclick=function(){sel.style.display='none';}
30                                                        </script>
31                                                    </div>
32                                                </TD>