如何获取多选框的所有选定值？

没有jQuery：

// Return an array of the selected opion values// select is an HTML select elementfunction getSelectValues(select) {  var result = [];  var options = select && select.options;  var opt;  for (var i=0, iLen=options.length; i<iLen; i++) {    opt = options[i];    if (opt.selected) {      result.push(opt.value || opt.text);    }  }  return result;}

快速示例：

<select multiple>  <option>opt 1 text  <option value="opt 2 value">opt 2 text</select><button onclick="  var el = document.getElementsByTagName('select')[0];  alert(getSelectValues(el));">Show selected values</button>