写在前面：这个只是对小程序提供的API进行了简单的封装，并没有什么特别牛的技术，记录下小程序的开发过程而已

感谢参考，再次感谢！
小程序请求部分的信息

需求

1.设置最大图片数，选满后添加按钮消失；
2.支持选择后删除图片；
3.查看大图；
4.上传图片到指定服务器；

如何使用

1.把文件拖到项目里
2.使用upload-image
3.完成。。。。

关键代码:

// upload-image.js
import {
  httpUtil,
  LogUtil,
} from '../../../../utils/utils.js'

Component({
  /**
   * 组件的属性列表
   */
  properties: {
    maxCount: {
      type: Number,
      value: 6,
      observer: function(newVal, oldVal) {
        this.setData({
          currentLastCount: newVal
        });
      }
    }
  },

  /**
   * 组件的初始数据
   */
  data: {
    currentLastCount: 0,
    images: []
  },


  /**
   * 组件的方法列表
   */
  methods: {
    addImage() {
      wx.chooseImage({
        sizeType: ['original', 'compressed'], //可选择原图或压缩后的图片
        sourceType: ['album', 'camera'], //可选择性开放访问相册、相机
        success: res => {
          const tempFilePaths = this.data.images.concat(res.tempFilePaths)
          var tempImages = []
          for (var i = 0; i < tempFilePaths.length; i++) {
            var image = {
              path: tempFilePaths[i],
              value: {
                uploaded: false,
                uploadStatus: "defaultStatus",
                url: ''
              }
            }
            tempImages.push(image)
            console.log('tempImages' + tempImages)
          }
          this.setData({
            images: tempImages.length <= this.data.maxCount ? tempImages : tempImages.slice(0, this.data.maxCount),
            currentLastCount: this.data.maxCount - tempImages.length,
          })

          for (var i = 0; i < tempImages.length; i++) {
            this.uploadpicture(tempImages[i])
          }
        }
      })
    },

    /**
     * 上传图片
     */
    uploadpicture(image) {
      console.log('上传之前的image', image)
      var thatImages = this.images;
      const success = function(data) {
        console.log('上传成功的image', image)
        if (data && data.length > 0) { ////自己替换
          const model = data[0];
          const url = model.key;
          // for (var i = 0; i < thatImages.length; i++) {
          //   if (thatImages[i].path === image.path) {
              image.value.uploaded = true;
              image.value.uploadStatus = 'success';
              if (url) {
                image.value.url = url
              }
              // thatImages[i] = image
              this.setData({
                images: [image],
              })
          //   }
          // }
          console.log('修改之后的image' + image)
        }
      }

      const fail = function(e) {
        console.log(e)
      }

      const progress = function(res) {
        console.log('上传进度', res.progress + image.path + image.uploadStatus + image.uploaded)

      }
      httpUtil.uploadFile(image.path, success, fail, progress)
    },

    removeImage(e) {
      const idx = e.target.dataset.idx;
      this.data.images.splice(idx, 1);
      this.setData({
        images: this.data.images,
        currentLastCount: this.data.maxCount - this.data.images.length
      })
    },

    handleImagePreview(e) {
      const idx = e.target.dataset.idx
      const images = this.data.images
      wx.previewImage({
        current: images[idx], //当前预览的图片
        urls: images, //所有要预览的图片
      })
    }
  }
})