layui 图片与表单一起提交 + layer.photos图片层预览

HTML基本结构：

<form class="layui-form" action="" id="feedBackForm">
        <div class="layui-form-item">
        <!--表单内容-->
        </div>

        <!--图片上传-->
        <div class="layui-upload feedback-padding">
        <button type="button" class="layui-btn" id="selectImg">选择图片</button>
        <input type="text" class="layui-hide" name="">
        <blockquote class="layui-elem-quote layui-quote-nm" style="margin-top: 10px;">
        预览图：
    <div id="previewImg" class="layui-clear feedback-overflow">
        </div>
        </blockquote>
        </div>

        <div class="layui-form-item">
        <div class="feedback-block">
        <button id="submitBtn" class="layui-btn" lay-submit="" lay-filter="demo1">立即提交</button>
        </div>
        </div>
        </form>

JavaScript基本内容：

1、多图片上传、预览

    //多图片上传
    uploadList = upload.render({
        elem: '#selectImg'
        ,url: "/add.do"
        ,accept: 'images'
        ,acceptMime: 'image/*'
        ,method: 'post'
        ,multiple: true
        ,auto: false
        ,choose: function(obj){
            files = obj.pushFile(); //将每次选择的文件追加到文件队列

            //图像预览，如果是多文件，会逐个添加。(不支持ie8/9)
            obj.preview(function(index, file, result){
                var imgBox = document.createElement("div");//预览图、删除预览图按钮容器
                var imgDelete = document.createElement("div");//删除预览图按钮
                var imgobj = new Image(); //创建新img对象

                imgBox.style.float = 'left';
                imgBox.style.position = 'relative';

                imgDelete.setAttribute('class',"feedback-delete-btn layui-icon layui-icon-close-fill");
                imgDelete.setAttribute ('title','删除');

                imgobj.src = result; //指定数据源
                imgobj['layer-src'] = result;
                imgobj.alt = file.name;
                imgobj.className = 'layui-upload-img';
                imgobj['layer-index'] = index;

                imgBox.appendChild(imgobj);
                imgBox.appendChild(imgDelete);

                imgDelete.onclick = function () { // 为预览图的删除按钮绑定删除事件
                    delete files[index]; //删除对应的文件
                    document.getElementById("previewImg").removeChild(imgBox);//从预览区域移除
                    uploadList.config.elem.next()[0].value = ''; //清空 input file 值，以免删除后出现同名文件不可选
                }

                document.getElementById("previewImg").appendChild(imgBox); //添加到预览区域

                //photos 图片层
                layer.photos({//此处目前存在bug 导致单击后无法在弹层中打开预览  下面会讲解如何处理
                    photos: '#previewImg'
                    ,anim: 0
                });
            });
        }
    });

2、提交

    //监听提交
    form.on('submit(demo1)', function(data){
        var myForm = document.getElementById("feedBackForm");
        var formData = new FormData(myForm);

        //循环 files(第一步choose回调中储存的对象)  逐条插入到formData
        for (var i in files) {
            formData.append("files",files[i]);//此处的files为上传接口参数名
        }

        $.ajax({
            url: "/add.do",
            type: "POST",
            data: formData,
            async: false,
            contentType: false,
            processData: false,
            error: function () {
                layer.msg('网络超时',{icon:2});
            },
            success: function (data) {
                layer.msg('成功',{icon:1});
            }
        })
        return false;
    });

3、步骤一中  layer.photos 重复调用，导致弹层预览图无法正常显示处理：

修改layer.js源码 ，点击事件绑定之前，先用off（）进行解绑，避免重复绑定，如下：

    loop || parent.off('click').on('click', options.img, function(){
        var othis = $(this), index = othis.attr('layer-index');
        layer.photos($.extend(options, {
            photos: {
                start: index,
                data: data,
                tab: options.tab
            },
            full: options.full
        }), true);
        pushData();
    })