<div>

    <input type="file" name="FileUpload" id="FileUpload" value="上传文件" />

    <a onclick="uploadFile()">提交</a>

</div>

<script>

    //说明：上传文件必须为xls或xlsx格式

    //input绑定change事件

    var FileUpload = document.getElementById("FileUpload");

    FileUpload.addEventListener("change",function(){

        var name = FileUpload.files[0].name;

        var i = name.lastIndexOf(".")

        if(i>-1){

            var ext = name.substring(i);

            var index = [".xls",".xlsx"].indexOf(ext);

            if(index==-1){

                alert("文件格式错误")

                FileUpload.value="";

            }

        }

    })

    //提交

    uploadFile(){

        var fileObj = document.getElementById("FileUpload").files[0]; // js 获取文件对象

        if (typeof (fileObj) == "undefined" || fileObj.size <= 0) {

            alert("请选择图片");

            return;

        }

        var formFile = new FormData();

        formFile.append("file", fileObj); //加入文件对象

        $.ajax({

            url: "",

            data: formFile,

            type: "Post",

            dataType: "json",

            cache: false,//上传文件无需缓存

            processData: false,//用于对data参数进行序列化处理 这里必须false

            contentType: false, //必须

            success: function (result) {

               alert("上传完成!");

           }

        })

    }

</script>