cordova-plugin-file 文件操作整理（三）

Cordove File实例Demo（二）

window.resolveLocalFileSystemURL（folder,successCB,errorCB）

获取系统目录/文件的操作实例FileEntry，DirectoryEntry

folder：路径file:///协议的目录位置或文件位置，可以自己拼接，可以使用cordova.file中定义的路径，示例：file:///storage/emulated/0/Android/data/

cordova中FileEntry多了个nativeURL，为当前系统中的位置。

使用实例：

window.resolveLocalFileSystemURL(cordova.file.dataDirectory, function (dirEntry) {      console.log('file system open: ' + dirEntry.name);      var isAppend = true;      createFile(dirEntry, "fileToAppend.txt", isAppend);  }, onErrorLoadFs);  
1.读取系统目录内容：
//获取当前程序存储目录$scope.show3 = function () {    $scope.folder = cordova.file.applicationStorageDirectory;    console.info(cordova.file.applicationStorageDirectory);    console.info($scope.folder);}//外部存储目录$scope.show4 = function () {    $scope.folder = cordova.file.externalApplicationStorageDirectory;}//获取系统，指定文件夹内容$scope.show2 = function () {    console.info($scope.folder);    //显示根目录内容    window.resolveLocalFileSystemURI($scope.folder, function (dirEntry) {        //显示根目录下的内容        var dirReader = dirEntry.createReader();        var entries = [];        var readEntries = function () {            //返回FileEntry数组            dirReader.readEntries(function (results) {                if (!results.length) {                    showEntries(entries.sort());                } else {                    entries = entries.concat(toArray(results));                    readEntries();                }            }, errorHandler);        }        readEntries();    });    function errorHandler(err) {        console.info(err);    }    function toArray(list) {        return Array.PRototype.slice.call(list || [], 0);    }    //显示读取结果    function showEntries(entries) {        console.info(entries);    }}2.下载图片到程序的系统目录
$scope.download1 = function () {    //如果目录不存在异常：Wrong type for parameter "uri" of resolveLocalFileSystemURI: Expected String, but got Undefined.    window.resolveLocalFileSystemURI($scope.folder, function (dirEntry) {        getSampleFile(dirEntry);    }, errorHandle);    //下载图片到程序    function getSampleFile(dirEntry) {        console.info(dirEntry);        //1.请求png 图片        var xhr = new xmlHttpRequest();        xhr.open('GET', 'http://cordova.apache.org/static/img/cordova_bot.png', true);        xhr.responseType = 'blob';        xhr.onload = function () {            if (this.status == 200) {                var blob = new Blob([this.response], { type: 'image/png' });                //保存                saveFile(dirEntry, blob, 'downloadImage.png');            }        }        xhr.send();    }    //保存到本地    function saveFile(dirEntry, blob, filename) {        console.info(blob);        //创建文件        dirEntry.getFile(filename, { create: true }, function (fileEntry) {            fileEntry.createWriter(function (fileWriter) {                fileWriter.onwriteend = function () {                    console.log('写入文件成功');                    if (blob.type == 'image/png') {                        readBinaryFile(fileEntry);                    } else {                        console.error(blob);                    }                }                fileWriter.onerror = function (err) {                    console.error('写入文件失败：' + err.toString());                }                fileWriter.write(blob);            });        }, errorHandle);    }    //读取二进制文件    function readBinaryFile(fileEntry) {        fileEntry.file(function (file) {            var reader = new FileReader();            reader.onloadend = function () {                //显示图片文件                console.info(fileEntry.nativeURL);                var blob = new Blob([new Uint8Array(reader.result)], { type: 'image/png' });                $scope.imgOne = window.URL.createObjectURL(blob);                $scope.$apply();            }            reader.readAsArrayBuffer(file);        }, errorHandle);        //直接显示图片        $scope.imgTwo = fileEntry.toURL();        $scope.$apply();    }}更多：
cordova-plugin-file 文件操作整理（二）
cordova-plugin-file 文件操作整理（一）
cordova-plugin-vibration 设备震动整理
http://www.hangge.com/blog/cache/detail_1179.html