客户端限制只能上传jpg格式图片的js代码

代码如下: function checkPhoto(fnUpload) { var filename = fnUpload.value; alert(filename); var mime = filename.toLowerCase().substr(filename.lastIndexOf(“.”)); if(mime!=”.jpg”) { alert(“请选择jpg格式的照片上传”); fnUpload.outerHTML=fnUpload.outerHTML; } }