<script>
function doit(obj){
var i = obj.selectedIndex;
if (i==0) return false;
s = obj.options[i].value;
document.getElementById("t1").value= s;
return true;
}
</script><form name="form1">
<select name="select2" onchange="doit(this);">
<option value="0">请选择</option>
<option value="1">xxx</option>
</select>
<input type="text" id = "t1">
</form>
function doit(obj){
var i = obj.selectedIndex;
if (i==0) return false;
s = obj.options[i].value;
document.getElementById("t1").value= s;
return true;
}
</script><form name="form1">
<select name="select2" onchange="doit(this);">
<option value="0">请选择</option>
<option value="1">xxx</option>
</select>
<input type="text" id = "t1">
</form>
我用这个方法的时候总出现undefind
是怎么回事?
function fn(obj)
{
oInput = document.getElementById("in");
if(obj.selectedIndex == 0)
oInput.value = "";
else
oInput.value = obj.options[obj.selectedIndex].text;
}
</script><input id="in" type="text">
<select id="se" onchange="javascript:fn(this);">
<option>请选择</option>
<option>aaa</option>
<option>bbb</option>
</select>
var i = 0;
function fn(obj)
{
var oInput = document.getElementById("in");
if(obj.selectedIndex == 0)
oInput.value = "";
else
oInput.value = obj.options[obj.selectedIndex].text;
}
function addOption()
{
var oSelect = document.getElementById("se");
var oOption = document.createElement("option");
oOption.text = i;
i++
oSelect.appendChild(oOption);
}
</script><input id="in" type="text">
<select id="se" onchange="javascript:fn(this);">
<option>请选择</option>
<option>aaa</option>
<option>bbb</option>
</select><input type="button" value="add option" onclick="javascript:addOption();">