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To remove an element inside an array, e.g. the element with the index 1. $fruit = array("bananas", "apples", "peaches"); unset($fruit[1]); This will remove the apples from the list, but notice that unset does not change the indexes of the remaining elements. So $fr...

Boolean is a type, having two values, denoted as true or false. This code sets the value of $foo as true and $bar as false: $foo = true; $bar = false; true and false are not case sensitive, so TRUE and FALSE can be used as well, even FaLsE is possible. Using lower case is most common and recom...

A cookie is set using the setcookie() function. Since cookies are part of the HTTP header, you must set any cookies before sending any output to the browser. Example: setcookie("user", "Tom", time() + 86400, "/"); // check syntax for function params Description: ...

Retrieve and Output a Cookie Named user The value of a cookie can be retrieved using the global variable $_COOKIE. example if we have a cookie named user we can retrieve it like this echo $_COOKIE['user'];

The value of a cookie can be modified by resetting the cookie setcookie("user", "John", time() + 86400, "/"); // assuming there is a "user" cookie already Cookies are part of the HTTP header, so setcookie() must be called before any output is sent to the...

Use the isset() function upon the superglobal $_COOKIE variable to check if a cookie is set. Example: // PHP <7.0 if (isset($_COOKIE['user'])) { // true, cookie is set echo 'User is ' . $_COOKIE['user']; else { // false, cookie is not set echo 'User is not logged in'; } ...

cat < file.txt Output is same as cat file.txt, but it reads the contents of the file from standard input instead of directly from the file. printf "first line\nSecond line\n" | cat -n The echo command before | outputs two lines. The cat command acts on the output to add line num...

# Length of a string $ var='12345' $ echo "${#var}" 5 Note that it's the length in number of characters which is not necessarily the same as the number of bytes (like in UTF-8 where most characters are encoded in more than one byte), nor the number of glyphs/graphemes (some of which ...

An element can be cloned by invoking the cloneNode method on it. If the first parameter passed to cloneNode is true, the children of the original will also be cloned. var original = document.getElementsByTagName("li")[0]; var clone = original.cloneNode(true);

Many databases allow to make the primary key value automatically increment when a new key is added. This ensures that every key is different. MySQL CREATE TABLE Employees ( Id int NOT NULL AUTO_INCREMENT, PRIMARY KEY (Id) ); PostgreSQL CREATE TABLE Employees ( Id SERIAL PRIMARY...

This will draw a line at the bottom of every view but the last to act as a separator between items. public class SeparatorDecoration extends RecyclerView.ItemDecoration { private final Paint mPaint; private final int mAlpha; public SeparatorDecoration(@ColorInt int color, float w...

The class template std::shared_ptr defines a shared pointer that is able to share ownership of an object with other shared pointers. This contrasts to std::unique_ptr which represents exclusive ownership. The sharing behavior is implemented through a technique known as reference counting, where the...

Instances of std::weak_ptr can point to objects owned by instances of std::shared_ptr while only becoming temporary owners themselves. This means that weak pointers do not alter the object's reference count and therefore do not prevent an object's deletion if all of the object's shared pointers are ...

Function overloading is having multiple functions declared in the same scope with the exact same name exist in the same place (known as scope) differing only in their signature, meaning the arguments they accept. Suppose you are writing a series of functions for generalized printing capabilities, b...

A std::vector can be initialized in several ways while declaring it: C++11 std::vector<int> v{ 1, 2, 3 }; // v becomes {1, 2, 3} // Different from std::vector<int> v(3, 6) std::vector<int> v{ 3, 6 }; // v becomes {3, 6} // Different from std::vector<int> v{3, ...

You can iterate over a std::vector in several ways. For each of the following sections, v is defined as follows: std::vector<int> v; Iterating in the Forward Direction C++11 // Range based for for(const auto& value: v) { std::cout << value << "\n"; } /...

There are several ways to use a std::vector as a C array (for example, for compatibility with C libraries). This is possible because the elements in a vector are stored contiguously. C++11 std::vector<int> v{ 1, 2, 3 }; int* p = v.data(); In contrast to solutions based on previous C++ st...

The jQuery function (usually aliased as $) can be used both to select elements and to create new elements. var myLink = $('<a href="http://stackexchange.com"></a>'); You can optionally pass a second argument with element attributes: var myLink = $('<a>', { 'href': 'h...

String html = "<!DOCTYPE html>" + "<html>" + "<head>" + "<title>Hello world!</title>" + "</head>" + "<body>" + ...

When you make a label and set its text to be more than a single line that it can display, it will be truncated and you will see only one line of text ending with three dots (...). This is because a property called numberOfLines is set to 1, and therefore only one line will be displayed. It is a comm...