


[PHP] Back to the basics (IO flow) Basic knowledge of php for beginners php tutorial php hands-on
Jul 29, 2016 am 08:49 AMIOStreams are used to handle data transmission between devices
javaThe operation of data is through streams
javaThe objects used to operate streams are in the IO package
stream According to the operation data, it is divided into two types: byte stream and character stream. The stream is divided into two types according to the flow direction: input stream and output stream.
FileWriter object, newcomes out, construction parameter:
String file name; at this time, the file will be created in the specified directory, if it already exists, it will be overwritten; this method will throwIOExceptionExceptionCall the write() method of the FileWriter object to write the string into the stream. Parameters: String
StringCall FileW riter Object's flush() method, refresh stream
FileWriter fw=<span>new</span> FileWriter("test.txt"<span>); fw.write(</span>"hello3"<span>); fw.close();</span><span>//</span><span>刷新并關(guān)閉</span>
file operation, read get FileReader object, new
come out, construction parameters: String’s files The name
calls the read() method of the FileReader object to return the read length. If it reaches the end, it will return -1
. Parameter:char[] character array whileLoop reading, condition: if the read length is not -1combination string
FileReader fr=<span>new</span> FileReader("test.txt"<span>); </span><span>char</span>[] buf=<span>new</span><span>char</span>[2<span>]; </span><span>int</span> len=0<span>; StringBuilder sb</span>=<span>new</span><span> StringBuilder(); </span><span>while</span>((len=fr.read(buf))!=-1<span>){ sb.append(</span><span>new</span> String(buf,0<span>,len)); } System.out.println(sb.toString());</span>PHP version, file operation, write
call function fopen(), Open the file to get the
file object, parameters: String file name,"w" to write, if the file does not exist, it will be created Call the fwrite() method to write directly to the file Inside, parameters: file object, String
stringcall fclose() method to close the stream, parameters: file object
<span>$file</span>=<span>fopen</span>("test.txt","w"<span>); </span><span>fwrite</span>(<span>$file</span>,"hello"<span>); </span><span>fclose</span>(<span>$file</span>);
File operation, read call function fopen(), open the file to get
file object, parameters: Stringfile name, ”r” read call function fread(), get the string of String, parameters: file
object, read lengthwhile loop reading, condition: not to the end of the file, feof($ file) is not concatenated string<span>$file</span>=<span>fopen</span>("test.txt","r"<span>);
</span><span>$str</span>=""<span>;
</span><span>while</span>(!<span>feof</span>(<span>$file</span><span>)){
</span><span>$str</span>.=<span>fread</span>(<span>$file</span>, 1<span>);
}
</span><span>echo</span><span>$str</span><span>;
</span><span>fclose</span>(<span>$file</span>);
fortrue
The above introduces [PHP] Back to the Basics (IO Flow), including PHP and basic aspects. I hope it will be helpful to friends who are interested in PHP tutorials.

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