使用wx.getFileSystemManager().readFileSync(url, 'base64')做base64上传，但是上传失败

let base64 = wx.getFileSystemManager().readFileSync(url, 'base64')  

uploadImg(data) {  
                uni.uploadFile({  
                    header: {  
                        sign: this.$store.getters.sign  
                    },  
                    formData: {  
                        type: 'image/png'  
                    },  
                    fileType: 'image',  
                    url: apiurl + this.url,  
                    file: data,  
                    name: 'imgBase64',  
                    success: (uploadFileRes) => {  
                        console.log(uploadFileRes,999)  
                        // let data = JSON.parse(uploadFileRes.data)  
                        // this.imageSrc = data.data;  
                        // this.$load.close()  
                        // this.showImg = false  
                        this.$alertinfo('上传成功')  
                    }  
                })  

            },  

获取图片将图片转为base64上传，上传的api没有任何反应