base64src(base64data, cb) {

            const FILE_BASE_NAME = 'tmp_base64src'; //自定义文件名

            const [, format, bodyData] = /data:image\/(\w+);base64,(.*)/.exec(base64data) || [];

            if (!format) {

                return (new Error('ERROR_BASE64SRC_PARSE'));

            }

            const filePath = `${wx.env.USER_DATA_PATH}/${FILE_BASE_NAME}.${format}`;

            const fsm = wx.getFileSystemManager();

            fsm.writeFile({

                filePath,

                data: bodyData,

                encoding: 'base64',

                success() {

                    cb(filePath);

                },

                fail() {

                    return (new Error('ERROR_BASE64SRC_WRITE'));

                },

            });

        };

​

​

                            this.base64src(base64, res => {

                                console.log('返回图片地址>>>>>>>>>>',res) // 返回图片地址，直接赋值到image标签即可

                                wx.previewImage({

                                    urls: [res],

                                    success: () => {

                                        try {

                                            wx.setStorageSync(key, res);

                                        } catch (e) {

                                            this.syncKeyImage[key] = res;

                                        }

                                    }

                                })

                            });