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How to initialize static variables
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PHP can't parse non-trivial expressions in initializers.
I prefer to work around this by adding code right after definition of the class:
class Foo {
static $bar;
}
Foo::$bar = array(…);
or
class Foo {
private stat...
Get the first element of an array
... a array "copy" is needed:
array_shift(array_slice($array, 0, 1));
With PHP 5.4+ (but might cause an index error if empty):
array_values($array)[0];
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Checking if an instance's class implements an interface?
... "Yes!";
}
class_implements() is part of the SPL extension.
See: http://php.net/manual/en/function.class-implements.php
Performance Tests
Some simple performance tests show the costs of each approach:
Given an instance of an object
Object construction outside the loop (100,000 iterations)
_...
Learning Regular Expressions [closed]
...ore characters, and terminated by a right-parenthesis.
If your input is '(123) (456)', then the first capture will be '123'. Non-greedy quantifiers want to allow the rest of the pattern to start matching as soon as possible.
(As to your confusion, I don't know of any regular-expression dialect whe...
How to select where ID in Array Rails ActiveRecord without exception
...ore relevant for Rails 4.x
Do this:
current_user.comments.where(:id=>[123,"456","Michael Jackson"])
The stronger side of this approach is that it returns a Relation object, to which you can join more .where clauses, .limit clauses, etc., which is very helpful. It also allows non-existent IDs ...
Adding :default => true to boolean in existing Rails column
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change_column :things, :price_1, :integer, default: 123, null: false
Seems to be best way to add a default to an existing column that doesn't have null: false already.
Otherwise:
change_column :things, :price_1, :integer, default: 123
Some research I did on this:
https:...
How to prevent robots from automatically filling up a form?
...$(this).serialize();
alert( serializedData );
$.ajax({
url: '/mail.php',
type: "POST",
data: serializedData,
success: function (data) {
// log the data sent back from PHP
console.log( data );
}
});
}
.myForm input,
.myForm textarea{
font: 14px/1 sans-serif;
...
.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included i
I have this error when trying to browse php files locally
8 Answers
8
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How to debug PDO database queries?
Before moving to PDO, I created SQL queries in PHP by concatenating strings. If I got database syntax error, I could just echo the final SQL query string, try it myself on the database, and tweak it until I fixed the error, then put that back into the code.
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How can I implode an array while skipping empty array items?
Perl's join() ignores (skips) empty array values; PHP's implode() does not appear to.
9 Answers
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