juery實現文件上傳（ajax）

// 文件上傳
function uploadHeadpic(){
    var formData = new FormData();
    formData.append('file', $('#file')[0].files[0]);
    formData.append("username",loginUser2.username);
    formData.append("uploadIp",returnCitySN["cip"]);
    formData.append("uploadLocation",currLocation);
    console.log(formData);
    //ajax請求
    $.ajax({
        url:"http://localhost:10004/headpic/upload",
        data:formData,
        dataType:"text",
        type:"post",
        // 以下兩個屬性必須設置！！！！
        contentType: false,
        processData: false,
        success:function (response) {
            alert(response.message);
            // 刷新歷史提頭像和當前頭像
        }
    })
}