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How do I convert a PDF document to a preview image in PHP? [closed]
...
You need ImageMagick and GhostScript
<?php
$im = new imagick('file.pdf[0]');
$im->setImageFormat('jpg');
header('Content-Type: image/jpeg');
echo $im;
?>
The [0] means page 1.
sha...
How to search by key=>value in a multidimensional array in PHP
...lue; the ampersand & is crucial.
FYI: If you have an older version of PHP then you have to specify the pass-by-reference part in the call to search_r rather than in its declaration. That is, the last line becomes search_r($subarray, $key, $value, &$results).
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Can “using” with more than one resource cause a resource leak?
...What happens if font4 = new Font() throws after the unmanaged resource was allocated by the constructor but before the ctor returns and fills in font4 with the reference?
Let me make that a little bit more clear. Suppose we have:
public sealed class Foo : IDisposable
{
private int handle = 0;...
PHP: How to remove all non printable characters in a string?
... a variety string lengths with random data, and this pattern emerged using php 7.0.12
2 chars str_replace 5.3439ms preg_replace 2.9919ms preg_replace is 44.01% faster
4 chars str_replace 6.0701ms preg_replace 1.4119ms preg_replace is 76.74% faster
8 chars str_replace ...
Best way to test for a variable's existence in PHP; isset() is clearly broken
...f isset().
Since this is takes the array to check as a function argument, PHP will still raise "notices" if the array itself doesn't exist. In some cases, it can validly be argued that each dimension should have been initialised first, so the notice is doing its job. For other cases, a "recursive" ...
Why was “Avoid Enums Where You Only Need Ints” removed from Android's performance tips?
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TLDR: Dalvik was not good with memory allocation and Enum uses more memory than int. Android Lollipop replaced Dalvik with ART which does not suffer from the same limitations. Thus this recommendation is not relevant anymore.
The long answer:
Wow! 8 years, 5 a...
Difference between a “coroutine” and a “thread”?
...d for a certain amount time (on a single processor machine). The scheduler allocates time (timeslicing) to each thread, and if the thread isn't finished within that time, the scheduler pre-empts it (interrupts it and switches to another thread). Multiple threads can run in parallel on a multi-proce...
How to replace part of string by position?
.... The StringBuilder approach avoid this extra cost by working within a pre-allocated section of memory and moving chars round within it.
– redcalx
Apr 17 '18 at 15:52
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How to disable XDebug
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Find your php.ini and look for XDebug.
Set xdebug autostart to false
xdebug.remote_autostart=0
xdebug.remote_enable=0
Disable your profiler
xdebug.profiler_enable=0
Note that there can be a performance loss even with xdebug di...
Authoritative position of duplicate HTTP GET query keys
...ive you as an array (I have not cared about the order when I tested that), PHP will give you always the last and Java (at least the system I worked with based on Java) always the first value. stackoverflow.com/questions/1809494/…
– SimonSimCity
Mar 8 '12 at 7...