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export function createFile() {
// 获取应用文件路径
let context = getContext(this) as common.UIAbilityContext;
let filesDir = context.filesDir;
// 新建并打开文件
let file = fs.openSync(filesDir + '/test.txt', fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE);
// 写入一段内容至文件
let content = "static

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let writeLen = fs.writeSync(file.fd, content);
console.info("The length of str is: " + writeLen);
// 从文件读取一段内容
let buf = new ArrayBuffer(4096);
let readLen = fs.readSync(file.fd, buf, { offset: 0 });
let s = String.fromCharCode.apply(null, new Uint8Array(buf.slice(0, readLen)));
let d = decodeURIComponent(escape(s));
console.info("the content of file: " + d);
// 关闭文件
fs.closeSync(file);
}

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export function getFilesDir(): string {
// 获取应用文件路径
let context = getContext(this) as common.UIAbilityContext;
return context.filesDir;
}
//<路径前缀>/<加密等级>/base/files/
//表示 APP 内部存储的缓存目录，可读写，但是随时可能被清楚，不保证持久性，一般用作下载临时目录或者缓存目录。
export function getCacheDir(): string {
let context = getContext(this) as common.UIAbilityContext;
return context.cacheDir;
}
//将内容写入内存中
export function writeFile(fileName: string, content: string) {
// 新建并打开文件
let file = fs.openSync(getFilesDir() + "/" + fileName, fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE);
// 写入一段内容至文件
let writeLen = fs.writeSync(file.fd, content);
console.info("The length of str is: " + writeLen);
// 关闭文件
fs.closeSync(file);
}
//从文件中读取内容
export function readFile(fileName: string) {
// 打开文件
let srcFile = fs.openSync(getFilesDir() + "/" + fileName, fs.OpenMode.READ_WRITE);
// 读取源文件内容并写入至目的文件
let bufSize = 4096;
let readSize = 0;
let buf = new ArrayBuffer(bufSize);
let readLen = fs.readSync(srcFile.fd, buf, { offset: readSize });
while (readLen > 0) {
readSize += readLen;
readLen = fs.readSync(srcFile.fd, buf, { offset: readSize });
}
let s = String.fromCodePoint.apply(null, new Uint8Array(buf));
console.log("readFile=============s==" + s);
let d = decodeURIComponent(escape(s));
console.log("readFile=============d==" + d);
// 关闭文件
fs.closeSync(srcFile);
}
//以流的形式读取文件
export async function readIOFile(fileName: string) {
// 打开文件流
let inputStream = fs.createStreamSync(getFilesDir() + '/' + fileName, 'r+');
// 以流的形式读取源文件内容并写入目的文件
let bufSize = 4096;
let readSize = 0;
let buf = new ArrayBuffer(bufSize);
let readLen = await inputStream.read(buf, { offset: readSize });
readSize += readLen;
while (readLen > 0) {
readLen = await inputStream.read(buf, { offset: readSize });
readSize += readLen;
}
let s = String.fromCodePoint.apply(null, new Uint8Array(buf));
console.log("readFile=============s==" + s);
let d = decodeURIComponent(escape(s));
console.log("readFile=============d==" + d);
// 关闭文件流
inputStream.closeSync();
}

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04-19 18:15:58.074 1611 5120 E C01401/Bufferqueue: [nodict]<514>CheckBufferConfig: width or height is greater than 0, now is w 0 h 0
04-19 18:15:58.074 1611 5120 E C01401/Bufferqueue: [nodict](HEncoderSurface) AllocBuffer: Failure [1669], Reason: Alloc failed, then <400 invalid arguments>
04-19 18:15:58.074 1611 5120 E C01401/Bufferqueue: [nodict](HEncoderSurface) RequestBuffer: Fail to alloc or map Buffer[0 0] ret: 40001000, id: 6919192313868
04-19 18:15:58.074 19365 19554 E C01401/Bufferqueue: [nodict]<115>NativeWindowRequestBuffer: API failed, please check RequestBuffer function ret:40001000, Queue Id:6919192313868
04-19 18:15:58.074 19365 19554 E A0FF00/Xhey:C:EglRenderContext: EglRenderContext::SwapBuffers: Failed to SwapBuffers on EGLSurface 1, error is EGL_SUCCESS.

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bundleName:'com.example.xxx.settings' a
bilityName:'com.example.xxx.settings.MainAbility',
uri:'application_info_entry', //application_settings

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