直接看代码

var xmlhttp;
xmlhttp = new XMLHttpRequest();
xmlhttp.open("POST", ajaxUrl.getCode, true);
xmlhttp.responseType = "arraybuffer";
xmlhttp.onreadystatechange = function () {
    if (this.status == 200) {
        var imageType = xmlhttp.getResponseHeader("Content-Type");
        var blob = new Blob([xmlhttp.response], { type: imageType });
        var imageUrl = (window.URL || window.webkitURL).createObjectURL(blob);
        $('#image').attr("src", imageUrl);
    }
}
var formData = new FormData();
formData.append('url', 'xxx');
formData.append('scene', 'id=xxx');
xmlhttp.send(formData)