js获取所有被选中的checkbox值

<label for=""><span>1</span><input type="checkbox" value="1"></label> <label for=""><span>2</span><input type="checkbox" value="2"></label> <label for=""><span>3</span><input type="checkbox" value="3"></label> <label for=""><span>4</span><input type="checkbox" value="4"></label> <button>提交</button> <script> var oBtn = document.getElementsByTagName("button")[0]; oBtn.onclick = function(){ var oTxt = document.getElementsByTagName("input"); for (var i = 0; i < oTxt.length; i++) { if(oTxt[i].checked){ alert(oTxt[i].value); } } } </script>