Combo-Box值未传入AJAX

Question

想要在AJAX参数中传递4个值。前三个正常传递，但第四个给出了问题。我在AJAX中显示警告后知道了

<tr align="left">
                                    <td style="background-color:#1569C7;color:white;font-weight:bold;font-size:110%;border-style:outset;"><center><b>Test Conducted</b></center></td>
                                    <td><select onchange="javascript:type123(document.getElementById('fodate').value,document.getElementById('todate').value,document.getElementById('product').value);" id="testcond" name="testcond">
                        <option>--Select--</option>

                </select></td>
                                </tr>

AJAX代码：

<script language="javascript">
            var xmlHttp1=null;
            function type123(obj,obj1,obj2)
              {
            //alert(this.value);
            var type_value=document.getElementById('testcond').options.selectedIndex.value;
            var val1=obj;
            var val2=obj1;
            var val3=obj2;
           // var val4=obj3;
            alert(val1);
            alert(val2);
            alert(val3);
            alert(type_value);

Answer 1

而不是

var type_value=document.getElementById('testcond').options.selectedIndex.value;

您可以尝试使用此选项获取Combo-Box的选定值

var type_value=document.getElementById('testcond').value;<br/>alert(type_value);