首先新建一个js文件，并在全局引用，这样方便在使用到的页面随时调用，此方法可以控制是否转base64

/**
  * 递归压缩H5图片
  * @param url 图片路径
  * @param isReturnBase64 是否返回base64
  * @param callback 回调函数
  * @return
  */
function recursionCompressH5(url, isReturnBase64,callback) {
  uni.getImageInfo({
    src: url,
    success(res) {
      let canvasWidth = res.width; //图片原始长宽
      let canvasHeight = res.height;
      let img = new Image();
      img.src = res.path;
      let canvas = document.createElement("canvas");
      let ctx = canvas.getContext("2d");
      canvas.width = canvasWidth / 2;
      canvas.height = canvasHeight / 2;
      ctx.drawImage(img, 0, 0, canvasWidth / 2, canvasHeight / 2);
      canvas.toBlob(function (fileSrc) {
        let imgSrc = window.URL.createObjectURL(fileSrc);
        uni.getFileInfo({
          filePath: imgSrc,
            success: (resFileInfo => {
            if (resFileInfo.size > 1024 * 1024 * 0.1) {
              //压缩后大于50k就继续压缩
              recursionCompressH5(imgSrc, isReturnBase64,callback);
              return
            } else {
              //小于就转化base64
              let resultBase64 = canvas.toDataURL("image/png")
              uni.hideLoading();
              callback && callback(isReturnBase64 ? resultBase64: imgSrc)
            }
          }),
        });
      });
    }
  });
}
module.exports = {
    recursionCompressH5:recursionCompressH5
}

调用方法demo

/**
* 点击事件内部调用相机拍照事件
* @param {Object} e
 */
            handleFileUpload(item) {
                this.name = item.peopleName;
                this.peopleId = item.peopleId;
                let that = this;
                uni.chooseImage({
                    count: 1, //默认9
                    sizeType: ['original', 'compressed'], //可以指定是原图还是压缩图，默认二者都有
                    sourceType: ['camera'],
                    success: function(res) {
                        uni.showLoading({
                            title: '照片上传中',
                            mask:true
                        });
                        that.$img.recursionCompressH5(res.tempFilePaths[0], true, that.imgdata); //调用压缩方法
                    },
                    fail: function(res) {
                        console.log(res);
                    }
                });
            },

callback函数即可取到压缩后的图片base64格式

//压缩图片的callback函数
            imgdata(data) {
//data就是压缩后的路径
                 this.urlCode = data;
                  console.log(this.urlCode);
            },