yhb/pages/chat/file-save-manager.js

const MAX_SIZE = 10400000;
let wholeSize = 0;
setTimeout(() => {
    wx.getSavedFileList({
        success: savedFileInfo => {
            let {fileList} = savedFileInfo;
            !!fileList && fileList.forEach(item => {
                wholeSize += item.size;
            });
            // console.log(wholeSize, '总大小');

        }
    });
});
export default class FileSaveManager {
    constructor() {

    }

    static set(msg, localPath) {
        wx.setStorage({key: msg.saveKey, data: localPath})
    }

    static get(msg) {
        return wx.getStorageSync(msg.saveKey);
    }

    static saveFileRule({tempFilePath, success, fail}) {
        wx.getFileInfo({
            filePath: tempFilePath,
            success: tempFailInfo => {
                let tempFileSize = tempFailInfo.size;
                // console.log('本地临时文件大小', tempFileSize);
                if (tempFileSize > MAX_SIZE) {
                    !!fail && fail('文件过大');
                    return;
                }
                wx.getSavedFileList({
                    success: savedFileInfo => {
                        let {fileList} = savedFileInfo;
                        console.log('文件列表', fileList);
                        if (!fileList) {
                            !!fail && fail('获取到的fileList为空，请检查你的wx.getSavedFileList()函数的success返回值');
                            return;
                        }
                        //这里计算需要移除的总文件大小
                        let sizeNeedRemove = wholeSize + tempFileSize - MAX_SIZE;
                        if (sizeNeedRemove >= 0) {
                            //按时间戳排序，方便后续移除文件
                            fileList.sort(function (item1, item2) {
                                return item1.createTime - item2.createTime;
                            });
                            let sizeCount = 0;
                            for (let i = 0, len = fileList.length; i < len; i++) {
                                // console.log('移除的文件1', sizeCount);
                                if ((sizeCount += fileList[i].size) >= sizeNeedRemove) {
                                    for (let j = 0; j < i; j++) {
                                        // console.log('移除的文件2', fileList[j].filePath);
                                        wx.removeSavedFile({
                                            filePath: fileList[j].filePath,
                                            success: function () {
                                                wholeSize -= fileList[j].size;
                                                // console.log('移除成功', wholeSize);
                                            }
                                        });
                                    }
                                    break;
                                }
                            }
                        }

                        wx.saveFile({
                            tempFilePath: tempFilePath,
                            success: res => {
                                wholeSize += tempFileSize;
                                typeof success === "function" && success(res.savedFilePath);
                            },
                            fail: fail
                        });
                    },
                    fail: fail
                });
            }
        });
    }
}