Home > Article > Backend Development > Learning PHP requires divergent thinking to learn PHP
I think that in the process of learning, everyone should know how to "play" and create a sense of accomplishment. In that case, the learning effect and enthusiasm will be very high, and
you will like what you are learning more!
Example:
Today I learned the image function part of PHP and learned several functions. They are:
getimagesize()
array getimagesize ( string $filename [, array &$imageinfo ] )
getimagesize() function will measure any GIF, JPG, PNG, SWF, SWC, PSD, TIFF, BMP, IFF, JP2, JPX, JB2, JPC, XBM or WBMP image file size and returns the dimensions of the image as well as the file type and one can be used in regular HTML files The height/width text string in the IMG tag.
imagecreatefromgif()
resource imagecreatefromgif ( string $filename )
imagecreatefromgif() Returns an image identifier representing the image obtained from the given filename.
This means that in order to facilitate the use of this image resource in the future, this function returns an operation handle.
Similar functions include imagecreatefromjpeg(), imagecreatefrompng(). Of course there are many more. You can read the official online manual
imagecolorat()
int imagecolorat ( resource $image , int $x , int $y )
Returns the image specified The color index value of the pixel at the specified position in the graphic.
imagecolorsforindex()
array imagecolorsforindex ( resource $image , int $index )
This function returns an associative array with keys red, green, blue and alpha, containing the corresponding value of the specified color index.
Everyone may be sleepy after reading a stiff introduction, but please hold on!
So after learning these functions, how do you practice them?
Actually, after I learned these functions, I immediately thought of a very fun thing to do!
What is it? Guess~! ! ! !
Look at the code:
$url = "logo-yy.gif";
$size = getimagesize($url);
$width = $size[0];
$height = $size[1] ;
$im = imagecreatefromgif($url);
for($y=1;$y<$height;$y++){
for($x=1;$x<$width;$x++){
$color_index = imagecolorat($im, $x, $y);
$color_tran = imagecolorsforindex($im, $color_index);
echo("");
echo("love");
echo(" ");
}
echo("
");
}
?>
It should be noted that the function used in my program is imagecreatefromgif()
So the variable $url points to The file should be in GIF format. If you want to point to a file in JPG format, use imagecreatefromjpeg()
Of course we can write it together, because the first function can determine the format of the image, so I won’t write it here! ! Haha
Okay, if you have a PHP environment, hurry up and try what it is! Haha
It is not recommended to use too large pictures! A small logo would be nice!
Otherwise, don’t blame me for not telling you!
This example has no practical use! ! But he can inspire everyone’s joy of learning! !
Dedicated to those who are learning PHP!
The above has introduced that learning PHP requires divergent thinking to learn PHP, including the content of learning PHP. I hope it will be helpful to friends who are interested in PHP tutorials.