php生成小图_php 生成缩略图代码

php生成小图_php 生成缩略图代码 这是一款经典实用的生成小图的php代码，有专业素语来讲就是php 生成缩略图代码哦。

php教程生成小图_php 生成缩略图代码
这是一款经典实用的生成小图的php代码，有专业素语来讲就是php 生成缩略图代码哦。
*/

# 显示图形及连接

function showdir ($adirectory, $i)

{
global $browsedir;

$start = $i;

# 更改 $maxcols 及 $maximages 可改变每一页显示的小图的行数与列数。

$maxcols = 2;
$maximages = 6;
$maximages = $i + ($maximages - 3);

# 更改 $imagemaxwidth 及 $imagemaxheight 可改变显示小图的宽度与高度。

$imagemaxwidth = 100;
$imagemaxheight = 100;

# 计算高度与宽度的比例。

$imagemaxratio = $imagemaxwidth / $imagemaxheight;

$ndirectory = sizeof ($adirectory);
echo (table_start);
for ($i; $i<=$maximages;)
{
echo (row_start);
for ($icols=1; $icols<=$maxcols; $icols++)
{
echo (col_start);
$imagefilename = $adirectory[++$i];
if (strlen($imagefilename)>0)
{
$imagepath = $browsedir."//m.sbmmt.com/m/".$imagefilename;
$imagesize = getimagesize ($imagepath);
if ($imagesize)
{
$imagewidth = $imagesize[0];
$imageheight = $imagesize[1];
$imageratio = $imagewidth / $imageheight;
if ($imageratio > $imagemaxratio)
{
$imageoutputwidth = $imagemaxwidth;
$imageoutputheight = ceil ($imagemaxwidth/$imagewidth*$imageheight);
}
else if ($imageratio < $imagemaxratio)
{
$imageoutputheight = $imagemaxheight;
$imageoutputwidth = ceil ($imagemaxheight/$imageheight*$imagewidth);
} else
{
$imageoutputwidth = $imagemaxwidth;
$imageoutputheight = $imagemaxheight;
}

# 显示图形

echo (a_start.$imagepath.a_close);
echo (img_start.$imagepath.img_width.$imageoutputwidth.img_height.$imageoutputheight.img_end);
echo (line_break.$adirectory[$i]);
echo (a_end);
}
echo (col_end);
}
}
echo (row_end);
}
echo (table_end);
pagemenu ($browsedir, $ndirectory, $start);

}

function pagemenu ($browsedir, $ndirectory, $pg) {

echo "

page:";

$pg_num = 1;

for ($img_num = 0; $img_num <= $ndirectory;) {

if ($pg == $img_num) {
echo " *$pg_num ";
} else {
echo " $pg_num ";
}

# 建立其他页次的连接, 每页显示四张图, 故页数 $pg_num 每加 1 , $img_num 就加 4 。

$pg_num = $pg_num + 1;
$img_num = $img_num + 4;

}

echo "n";

}

function dirtoarray ($browsedir, $extensions)
{

$nextensions = sizeof ($extensions);
$idirectory = 0;
$directory = dir($browsedir);

while ($entry = $directory->read())
{
for ($i=1; $i<=$nextensions; $i++)
{
$compare = stristr ($entry, $extensions[$i]);
if (strlen($compare) == strlen($extensions[$i]))
{
$adirectory[++$idirectory] = $entry;
break;
}
}
}
$directory->close();
return $adirectory;
}

#主程序

#变量 $browsedir 为图形文件放置的位置。

$browsedir="./images";

# 允许浏览的图形文件扩展名, 放置於数组中, 可自行增加。

$extensions[1] = "jpeg";
$extensions[2] = "jpg";
$extensions[3] = "gif";
$extensions[4] = "png";
showdir (dirtoarray ($browsedir, $extensions), $start);

define ("line_break", "
");
define ("table_start", "

n");
define ("table_end", "n");
define ("row_start", " n");
define ("row_end", " n");
define ("col_start", " n ");
define ("col_end", "n n");
define ("img_start", "");
define ("img_width", " width=");
define ("img_height", " height=");
define ("a_start", '');
define ("a_end", "");
?>