input输入框，回车激活按钮事件代码

   <input type="text" name="输入框ID" id="输入框ID" onkeypress="if(event.keyCode==13) {btn.click();return false;}"/>
    <input type="submit" name="btn" id="btn" value="提交" onclick="alert(输入框ID.value);return false;" />

回车可迅速切换下一题：已验证

onkeydown=if(event.keyCode==13){event.keyCode=9}

<script type="text/javascript">

    document.onkeydown=function(event){

        var e=event||window.event;

        var keyCode=e.keyCode||e.which;//e.which 兼容FF

        var target=e.srcElement||e.target;

            if (keyCode ==13) {  

                var tabindex=target.tabIndex+1;

                if( tabindex==6) tabindex=1;

                document.getElementById('elem'+tabindex).focus();

            }

    }

</script>

   <form>

<input type="text" tabindex="1" id="elem1"  />

<input type="text" value="readonly" readonly="readonly" tabindex="-1" />

<input type="button" value="click" tabindex="2"  id="elem2" />

<input type="text" tabindex="3" id="elem3"  />

<select tabindex="4" id="elem4" >

    <option value="1">select</option>

  <option value="2">select2</option>

</select>

<input type="button" value="submit" tabindex="5" id="elem5" />

</form>