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Member '' cannot be accessed with an instance reference
...d some time before
its first use.
A static entity has one storage location allocated, and that is
shared by all who access that entity.
A static entity can only be accessed through its type name, not
through an instance of that type.
A static method does not have an implicit ‘this’ argument, as ...
How can I initialize base class member variables in derived class constructor?
...onstructor. It will first be default-initialized when the instance of B is allocated, then it will be assigned inside the B's constructor. But I also think the compiler can still optimize this.
– Violet Giraffe
Jan 10 '19 at 11:36
...
Using semicolon (;) vs plus (+) with exec in find
...ind . -name 'test*' -exec echo {} \;
./test.c
./test.cpp
./test.new
./test.php
./test.py
./test.sh
With a plus, the command echo is called once only. Every file found is passed in as an argument.
$ find . -name 'test*' -exec echo {} \+
./test.c ./test.cpp ./test.new ./test.php ./test.py ./test.s...
What does T&& (double ampersand) mean in C++11?
...just be destroyed; why not make use of the resources the temporary already allocated? In C++03, there's no way to prevent the copy as we cannot determine we were passed a temporary. In C++11, we can overload a move constructor:
foo(foo&& other)
{
this->length = other.length;
this...
From io.Reader to string in Go
...ing about "the most efficient way". Currently, the Go run-time will always allocate a new string when converting []byte to string. The reason for this is that the compiler doesn't know how to determine whether the []byte will be modified after the conversion. There is some room for compiler optimiza...
Sending HTTP POST Request In Java
....encode( rawData, "UTF-8" );
URL u = new URL("http://www.example.com/page.php");
HttpURLConnection conn = (HttpURLConnection) u.openConnection();
conn.setDoOutput(true);
conn.setRequestMethod("POST");
conn.setRequestProperty( "Content-Type", type );
conn.setRequestProperty( "Content-Length", String...
File to byte[] in Java
...
Basically you have to read it in memory. Open the file, allocate the array, and read the contents from the file into the array.
The simplest way is something similar to this:
public byte[] read(File file) throws IOException, FileTooBigException {
if (file.length() > MAX...
What's the difference between a web site and a web application? [closed]
...ites are primarily informational. In this sense, http://cnn.com and http://php.net are websites, not web applications.
Web applications primarily allow the user to perform actions. Google Analytics, gmail, and jslint are web applications.
They are not entirely exclusive. A university website lik...
Amazon S3 Change file download name
...t-disposition" while submit the file to S3, the SDK version is AWS SDK for PHP 3.x. here is the doc http://docs.amazonaws.cn/en_us/aws-sdk-php/latest/api-s3-2006-03-01.html#putobject
a piece of my code
public function __construct($config)
{
$this->handle = new S3Client([
...
Modify SVG fill color when being served as Background-Image
...server-side script, to make sure you also send the correct MIME header. In PHP this would be: <?php header('Content-type: image/svg+xml'); ?>
– slightlyfaulty
Aug 21 '14 at 10:53
...