1、accept
只能选择png和gif图片
<input id="fileId1" type="file" accept="image/png,image/gif" name="file" />2、multiple
多文件上传
<input id="fileId2" type="file" multiple="multiple" name="file" />
3.application/vnd.openxmlformats-officedocument.spreadsheetml.sheet Excel
