BYTE_STREAM --o| FILE : contains } SOCKET { string host int port BYTE_STREAM --o| SOCKET : receives } 在这个ER图中,我们可以看到字节流(BYTE_STREAM)与文件(FILE)和Socket(SOCKET)之间的关系。 ByteStream+byteArray data+int length+decode()FileReader+string filePath+readBytes()SocketReader+string...
out << QString("caizhiming"); out << QDate::fromString("1986/01/03", "yyyy/MM/dd"); out << (qint32)21; file.close(); file.setFileName("binary.file"); if(!file.open(QIODevice::ReadOnly)) { return -1; } QDataStream in(&file); QString name; QDate birthday; qint32 a...
In the example, we read 4, 20, and 10 characters from the file. $ ./read_characters.py Lost Illusions Beatrix H onorine Th Python readlineThe readline function reads until newline or EOF and return a single string. If the stream is already at EOF, an empty string is returned. If ...
file.read(1) if (next == '/'): break return "IGNORE" else: return "SYMBOL" return "SYMBOL" elif (self.current == " " or self.current == "\n"): return "IGNORE" elif (self.current == "'"): while(next != "'"): self.current = self.current + next return "STRING_CONST" ...
字符串是Python中最常用的数据类型,而且很多时候你会用到一些不属于标准ASCII字符集的字符,这时候代码就很可能抛出UnicodeDecodeError: ascii codec cant decode byte 0xc4 in position 10: ordinal not in range(128)异常。这种异常在Python中很容易遇到,尤其是在Python2.x中。
通常情况下,你会用到open()的第2个参数mode,它用字符串来表示,你想要用什么方式,来打开文件。默认值是r代表用read-only只读的方式,打开文件: withopen('dog_breeds.txt','r')asreader:# Further file processing goes here 除了r之外,还有一些mode参数值,这里只简要的列出一些常用的: ...
In [29]: help(file.read) Help on method_descriptor: read(...) read([size]) -> read at most size bytes, returned as a string. If the size argument is negative or omitted, read until EOF is reached. Notice that when in non-blocking mode, less data than what was requested may be...
print("Read String is : ", str) # 获取当前位置 print(f"Current I/O pointer position :{fo.tell()}") # 关闭文件 os.close( fd ) print("关闭文件") open()、os.open()、os.fdopen() open() 函数用于打开一个文件,创建一个文件对象 ...
b = b''#创建一个空的bytesb = byte()#创建一个空的bytes # (2) b = b'hello'#直接指定这个hello是bytes类型 # (3) b = bytes('string',encoding='编码类型')#利用内置bytes方法,将字符串转换为指定编码的bytesb = str.encode('编码类型')#利用字符串的encode方法编码成bytes,默认为utf-8类型byte...
StringIo,BytesIo均属于io包下(3.7环境),均用于像操作文件一样,临时在内存中缓存文本,两者 api与直接进行问下文件io的操作相似。StringIO跟ByteIo的区别在于前者写入字符串,后者写入二进 制。 #可以在一开始就赋值内容 from io import StringIO str_io= StringIO("hello world") print(str_io.readline()) st...