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What is an abstract class in PHP?
...ion prefixValue($prefix);
public function printOut() {
echo "Hello how are you?";
}
}
$obj=new AbstractClass();
$obj->printOut();
//Fatal error: Cannot instantiate abstract class AbstractClass
2. Any class that contains at least one abstract method must also be abstract: Abst...
Reset PHP Array Index
...
The array_values() function [docs] does that:
$a = array(
3 => "Hello",
7 => "Moo",
45 => "America"
);
$b = array_values($a);
print_r($b);
Array
(
[0] => Hello
[1] => Moo
[2] => America
)
...
Escape double quotes in a string
...ou have, or escape the " using backslash.
string test = "He said to me, \"Hello World\" . How are you?";
The string has not changed in either case - there is a single escaped " in it. This is just a way to tell C# that the character is part of the string and not a string terminator.
...
How to invoke the super constructor in Python?
...init__(self):
print "world"
class B(A):
def __init__(self):
print "hello"
super(B, self).__init__()
Python-3.x
class A(object):
def __init__(self):
print("world")
class B(A):
def __init__(self):
print("hello")
super().__init__()
super() is now equivalent to super(<cont...
How to print out a variable in makefile
... will pass to the shell:
.PHONY: all
all: ; $(info $$var is [${var}])echo Hello world
Now, what happens here is that make stores the entire recipe ($(info $$var is [${var}])echo Hello world) as a single recursively expanded variable. When make decides to run the recipe (for instance when you tell...
How do I specify new lines on Python, when writing on files?
...ly or within a single string, which is easier.
Example 1
Input
line1 = "hello how are you"
line2 = "I am testing the new line escape sequence"
line3 = "this seems to work"
You can write the '\n' separately:
file.write(line1)
file.write("\n")
file.write(line2)
file.write("\n")
file.write(line3)...
React.js: Identifying different inputs with one onChange handler
... state because it is composable by adding other values in your state:
var Hello = React.createClass({
getInitialState: function() {
return {input1: 0, input2: 0};
},
render: function() {
const total = this.state.input1 + this.state.input2;
return (
&...
Make a Bash alias that takes a parameter?
...bash variables in quotes. eg mv "$1" "$1.bak". without quotes, if $1 were "hello world", you would execute mv hello world hello world.bak instead of mv "hello world" "hello world.bak".
– orion elenzil
Jun 11 '15 at 16:17
...
How do I get a substring of a string in Python?
...
>>> x = "Hello World!"
>>> x[2:]
'llo World!'
>>> x[:2]
'He'
>>> x[:-2]
'Hello Worl'
>>> x[-2:]
'd!'
>>> x[2:-2]
'llo Worl'
Python calls this concept "slicing" and it works on more than j...
How to change the text on the action bar
...straction.
For example:
=> Normal way,
getActionBar().setTitle("Hello world App");
getSupportActionBar().setTitle("Hello world App"); // provide compatibility to all the versions
=> Customizing Action Bar,
For example:
@Override
public void setActionBar(String heading) {
//...