微信版本 7.0.14

安卓9

saveQrImage:function(){
    var imgSrc = this.data.qrcode+'==';
    var _base64_arr =  imgSrc.split(',');
    console.log( _base64_arr )
    var base64 ="";
    if( _base64_arr.length==2 ){
      base64 = _base64_arr[1]
    }else{
      base64 = _base64_arr[0]
    }
    //var base64 = imgSrc;
    base64.replace(" ","");
    var save = wx.getFileSystemManager();
    var number = Math.random();
    console.log( base64  )
    var buffer = wx.base64ToArrayBuffer(base64) 
    save.writeFile({
      filePath: wx.env.USER_DATA_PATH + '/pic' + number + '.jpg',
      // data: base64,
      // encoding: 'base64',
      data: buffer,
      //encoding: 'binary',
      success: res => {
        wx.saveImageToPhotosAlbum({
          filePath: wx.env.USER_DATA_PATH + '/pic' + number + '.jpg',
          success: function (res) {
            wx.showToast({
              title: '保存成功',
            })
          },
          fail: function (err) {
            console.log(err)
          }
        })
        console.log(res)
      }, fail: err => {
        console.log(err)
      }
    })
  }