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# imagecreatefrompng

(PHP 3>= 3.0.13, PHP 4 , PHP 5)

imagecreatefrompng -- Create a new image from file or URL

## Description

resource imagecreatefrompng ( string filename)

imagecreatefrompng() returns an image identifier representing the image obtained from the given filename.

imagecreatefrompng() returns an empty string on failure. It also outputs an error message, which unfortunately displays as a broken link in a browser. To ease debugging the following example will produce an error PNG:

示範 1. Example to handle an error during creation (courtesy vic at zymsys dot com)

`<?php
function LoadPNG($imgname)
{
$im = @imagecreatefrompng($imgname); /* Attempt to open */
if (!$im) { /* See if it failed */
$im = imagecreate(150, 30); /* Create a blank image */
$bgc = imagecolorallocate($im, 255, 255, 255);
$tc = imagecolorallocate($im, 0, 0, 0);
imagefilledrectangle($im, 0, 0, 150, 30, $bgc);
/* Output an errmsg */
imagestring($im, 1, 5, 5, "Error loading $imgname", $tc);
}
return $im;
}
?>`

> 心得:如果 fopen wrappers 已啟動，則可藉此函數把檔名當成URL使用。參考 fopen() 有更多關於如何指定檔名的細節和附錄 L支援URL協定的列表。

切記!
PHP 4.3.0 之前的 Windows PHP版本不支援由此函數存取遠端檔案，即使啟動allow_url_fopen選項。

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