示例：
html

<div class="layui-form-item">
                                    <label class="layui-form-label">头像</label>
                                    <div class="layui-input-inline">
                                        <input type="text" name="head" lay-verify="required" id="inputimgurl" placeholder="图片地址" value="123.jpg" class="layui-input">
                                    </div>
                                    <div class="layui-input-inline">
                                        <div class="layui-upload-list" style="margin:0">
                                            <img src="123.jpg" id="srcimgurl" class="layui-upload-img">
                                        </div>
                                    </div>
                                    <div class="layui-input-inline layui-btn-container" style="width: auto;">
                                        <button class="layui-btn layui-btn-primary" id="editimg">修改图片</button >
                                    </div>
                                    <div class="layui-form-mid layui-word-aux">头像的尺寸限定150x150px,大小在50kb以内</div>
                                </div>

js

layui.config({
        base: '/static/cropper/' //layui自定义layui组件目录
    }).use(['form','croppers'], function () {
        var $ = layui.jquery
            ,form = layui.form
            ,croppers = layui.croppers
            ,layer= layui.layer;

        //创建一个头像上传组件
        croppers.render({
            elem: '#editimg'
            ,saveW:150     //保存宽度
            ,saveH:150
            ,mark:1/1    //选取比例
            ,area:'900px'  //弹窗宽度
            ,url: "upload/uploadImg"  //图片上传接口返回和（layui 的upload 模块）返回的JOSN一样
            ,done: function(url){ //上传完毕回调
                $("#inputimgurl").val(url);
                $("#srcimgurl").attr('src',url);
            }
        });

    });

后台上传

//用的thinkphp5.x

public function uploadImg()
    {
        //获取文件对象
        $file = $this->request->file('file');
        //验证并上传
        $info = $file->validate(['size'=>'5242880','ext'=>'jpg,gif,png'])
            ->move('static/upload/admin');
        //判断是否成功
        if($info){
            $data['src'] = '/static/upload/admin/'.$info->getSaveName();
            $this->result($data,0,'上传成功');
        }else{
            $this->result('',200,$file->getError());
        }
    }