微信小程序上传多张图片-视频，预览图片

考虑到日常项目中还是比较常用的，就整理了一下这案例，可以上传指定数量的图片或视频；
使用可以查看小程序文档：
选择图片： wx.chooseImage
选择视频：wx.chooseVideo

wxml:

<view class='the-tit'>上传图片：</view>
<view class='share-pics'>
  <view class='slug-cons'>
    <view class='pics'>
      <view class='tp' wx:for="{{upImgArr}}" wx:key="item">
          <image mode='aspectFill' class='img' src='{{item.path}}' data-presrc="{{item.path}}" bindtap='previewImg' />
          <view class='delbtn' data-index="{{index}}" data-type="image" bindtap='delFile'>X</view>
      </view>
    </view>
    <view class='btn' wx:if="{{upFilesBtn}}"  data-type="image" bindtap='uploadFiles'></view>
  </view>
</view>

js:

// pages/uploadPic/uploadPic.js
const app = getApp();
var util = require('../../utils/util.js');
var upFiles = require('../../utils/upFiles.js');

Page({

  /**
   * 页面的初始数据
   */
  data: {
    upImgArr: [], //存图片
    upFilesBtn: true,
    maxUploadLen: 9,  //限制上传数量
  },

  // 选择图片或者视频
  uploadFiles(e) {
    var that = this,
      type = e.currentTarget.dataset.type,
      maxUploadLen = that.data.maxUploadLen;
    if (type == 'image') {
      upFiles.chooseImage(that, maxUploadLen);
    } else if (type == 'video') {
      upFiles.chooseVideo(that, maxUploadLen);
    }
  },

  // 删除上传图片 或者视频
  delFile(e) {
    let that = this;
    wx.showModal({
      title: '温馨提示',
      content: '您确认要删除这张图片吗？',
      success(res) {
        if (res.confirm) {
          let delNum = e.currentTarget.dataset.index,
            delType = e.currentTarget.dataset.type,
            upImgArr = that.data.upImgArr,
            upVideoArr = that.data.upVideoArr;
          if (delType == 'image') {
            upImgArr.splice(delNum, 1)
            that.setData({
              upImgArr: upImgArr
            })
          } else if (delType == 'video') {
            upVideoArr.splice(delNum, 1)
            that.setData({
              upVideoArr: upVideoArr
            })
          }

          let upFilesArr = upFiles.getPathArr(that);
          if (upFilesArr.length < that.data.maxUploadLen) {
            that.setData({
              upFilesBtn: true,
            })
          }
        } else if (res.cancel) {
          console.log('用户点击取消')
        }
      }
    })
  },

  // 预览图片
  previewImg(e) {
    let that = this,
      imgsrc = e.currentTarget.dataset.presrc,
      arr = that.data.upImgArr,
      preArr = [];
    arr.map(function (v, i) {
      preArr.push(v.path)
    })
    //console.log(preArr)
    wx.previewImage({
      current: imgsrc,
      urls: preArr
    })
  },
})

完整案例可访问：https://github.com/xiexikang/xcx-uploadPic-Vid