小程序文件上传，提示文件上传失败，报错errMsg:"uploadFile:fail exceed max upload connection count 10"， 微信这个下载接口是多线程的么？ 我就一个上传一张图片，为什么超过最大并发数？ [代码]chooseImg: [代码][代码]function[代码] [代码]() {[代码][代码]        [代码][代码]var[代码] [代码]that = [代码][代码]this[代码][代码];[代码][代码]        [代码][代码]wx.chooseImage({[代码][代码]            [代码][代码]count: 1,[代码][代码]            [代码][代码]sizeType: [[代码][代码]'compressed'[代码][代码]],[代码][代码]            [代码][代码]sourceType: [[代码][代码]'album'[代码][代码], [代码][代码]'camera'[代码][代码]],[代码][代码]            [代码][代码]success: [代码][代码]function[代码] [代码](res) {[代码][代码]                [代码][代码]that.upload(res.tempFilePaths[0]);[代码][代码]            [代码][代码]},[代码][代码]        [代码][代码]})[代码][代码]    [代码][代码]},[代码][代码]    [代码][代码]upload: [代码][代码]function[代码] [代码](path) {[代码][代码]        [代码][代码]wx.uploadFile({[代码][代码]            [代码][代码]url: [代码][代码]'https://xxxx/api/car/upload-car-image'[代码][代码],[代码][代码]            [代码][代码]filePath: path,[代码][代码]            [代码][代码]name: [代码][代码]'car_image'[代码][代码],[代码][代码]            [代码][代码]header: { [代码][代码]'content-type'[代码][代码]: [代码][代码]'multipart/form-data'[代码] [代码]},[代码][代码]            [代码][代码]formData: {[代码][代码]                [代码][代码]'attach_attr'[代码][代码]: 1[代码][代码]            [代码][代码]},[代码][代码]            [代码][代码]success: [代码][代码]function[代码] [代码](res) {[代码][代码]                [代码][代码]// success[代码][代码]                [代码][代码]console.log([代码][代码]"成功"[代码][代码])[代码][代码]                [代码][代码]console.log(res.data)[代码][代码]            [代码][代码]},[代码][代码]            [代码][代码]fail: [代码][代码]function[代码] [代码](res) {[代码][代码]                [代码][代码]// fail[代码][代码]                [代码][代码]console.log([代码][代码]"失败"[代码][代码], res)[代码][代码]            [代码][代码]},[代码][代码]            [代码][代码]complete: [代码][代码]function[代码] [代码]() {[代码][代码]                [代码][代码]// complete[代码][代码]                [代码][代码]console.log([代码][代码]"完成"[代码][代码])[代码][代码]            [代码][代码]}[代码][代码]        [代码][代码]})[代码][代码]    [代码][代码]},[代码]根本都没有连接服务器，就直接报错了