具有像素尺寸的 PHP 自动换行
我正在寻找一种使用 PHP 将文本包装到特定宽度的框中的方法.我收到了动态文本字符串和可变字体大小.
我找到了一个很好的方法，可以从这个线程中按照我想要的方式剪切文本:PHP 中长字的智能自动换行?>
使用此代码块:
function smart_wordwrap($string, $width = 10, $break = "
") {//在行长度上拆分问题词$pattern = sprintf('/([^ ]{%d,})/', $width);$输出 = '';$words = preg_split($pattern, $string, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);foreach ($words as $word) {if (false !== strpos($word, ' ')) {//正常行为，重建字符串$output .= $word;} 别的 {//计算当前行有多少个字符$wrapped = expand($break, wordwrap($output, $width, $break));$count = $width - (strlen(end($wrapped)) % $width);//填充当前行并添加一个中断$output .= substr($word, 0, $count) .$break;//包装问题单词中的所有剩余字符$output .= wordwrap(substr($word, $count), $width, $break, true);}}//包装最终输出return wordwrap($output, $width, $break);}
这很好用，但我需要找到一种方法将设置的像素尺寸(约束框)和字体大小输入到上面.上面的函数使用了字符数 - 如果字体大小很明显，字符数需要更大，反之亦然.
如果我有以下变量，我可以这样做吗?
$boxWidth = 200(px);$text = (动态字符串);$font = '自定义字体.ttf'$fontSize = (动态大小);我正在考虑对自动换行功能进行另一个循环.或者也许有一种方法可以编辑爆炸"，因为我不完全确定该功能是如何工作的.
解决方案As @Mark Baker 建议 我已经使用 imagettfbbox()
- 可以在此处 找到带有辅助函数的完整代码片段
- 我正在发布相关代码以供参考
//帮助在图像上渲染文本的实用函数
//返回渲染文本的预期宽度(以像素为单位)公共静态函数 getWidthPixels(string $text, string $font, int $font_size): int {//https://www.php.net/manual/en/function.imageftbbox.php#refsect1-function.imageftbbox-returnvalues$bbox = imageftbbox($font_size, 0, $font, " " . $text);返回 $bbox[2] - $bbox[0];}//返回一段文本的包装格式(带换行符)(打算在图像上呈现)//使用渲染的文本边界框的宽度公共静态函数 wrapTextByPixels(字符串 $text,int $line_max_pixels，整数 $font_size，字符串 $font): 细绳 {$words = expand(' ', $text);//将文本标记为单词$行 = [];//Array[Array[string]]: 存储单词行的数组$crr_line_idx = 0;//(从零开始)当前行的索引，在其中添加单词$crr_line_pixels = 0;//当前行的宽度(在其中添加单词)以像素为单位foreach ($words as $word) {//确定当前行的新宽度(以像素为单位)如果当前单词被添加到它(包括空格)$crr_line_new_pixels = $crr_line_pixels + ImageTextRenderUtils::getWidthPixels(' ' . $word, $font, $font_size);//确定当前单词的宽度(以像素为单位)$crr_word_pixels = ImageTextRenderUtils::getWidthPixels($word, $font, $font_size);如果($crr_word_pixels > $line_max_pixels){//如果当前单词本身太长而无法放入一行//那么我们别无选择:它仍然必须只放在单行中如果($crr_line_pixels == 0){//但只有当前行为空时才放入当前行$lines[$crr_line_idx] = array($word);$crr_line_idx++;} 别的 {//否则如果当前行非空，则将超长的单词放入换行符$crr_line_idx++;$lines[$crr_line_idx] = array($word);$crr_line_idx++;$crr_line_pixels = 0;}} else if ($crr_line_new_pixels > $line_max_pixels) {//否则如果当前行的新宽度(包括当前单词和空格)//超过最大允许宽度，则强制当前单词换行$crr_line_idx++;$lines[$crr_line_idx] = array($word);$crr_line_pixels = $crr_word_pixels;} 别的 {//else 如果当前单词(包括空格)可以放入当前行，则将其放在那里$lines[$crr_line_idx][] = $word;$crr_line_pixels = $crr_line_new_pixels;}}//上面的foreach循环结束后，$lines二维数组Array[Array[string]]//将包含分隔成行的单词以保留 $line_max_pixels//现在我们只需要将行(字串数组)拼接成一个连续的文本片段$concatenated_string = array_reduce($行，静态函数(字符串 $wrapped_text，数组 $crr_line):字符串 {返回 $wrapped_text .PHP_EOL .内爆(' ', $crr_line);},'');//上面将行拼接成单段文本的过程会不经意间//在开头添加一个额外的换行符 '
';所以我们必须删除它return StringUtils::removeFirstOccurrence($concatenated_string, "
");}I'm looking for a way to wrap text into a box of specific width using PHP. I have dynamic text strings coming in, and variable font sizes.
I found a great way to cut the text up the way I want it from this thread: Smarter word-wrap in PHP for long words?
Using this block of code:
function smart_wordwrap($string, $width = 10, $break = "
") {
// split on problem words over the line length
$pattern = sprintf('/([^ ]{%d,})/', $width);
$output = '';
$words = preg_split($pattern, $string, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);
foreach ($words as $word) {
if (false !== strpos($word, ' ')) {
// normal behaviour, rebuild the string
$output .= $word;
} else {
// work out how many characters would be on the current line
$wrapped = explode($break, wordwrap($output, $width, $break));
$count = $width - (strlen(end($wrapped)) % $width);
// fill the current line and add a break
$output .= substr($word, 0, $count) . $break;
// wrap any remaining characters from the problem word
$output .= wordwrap(substr($word, $count), $width, $break, true);
}
}
// wrap the final output
return wordwrap($output, $width, $break);
}
This works great, but I need to find a way to feed a set pixel dimension (the constraining box), and font size into the above. The above function is using a character count - and if the font-size is very small obviously the character count needs to be larger and vice versa.
Is there anyway I could do this if I have the following variables?
$boxWidth = 200(px);
$text = (dynamic string);
$font = 'customfont.ttf'
$fontSize = (dynamic size);
I was thinking another loop to the word wrap function. Or maybe there's a way to edit the "explode" as I'm not entirely sure how that function works.
解决方案As suggested by @Mark Baker I have implemented this behaviour using imagettfbbox()
- Complete code-snippet with helper functions can be found here
- I'm posting the relevant bits of code for reference
// utility functions to help text rendering on image
// Returns expected width of rendered text in pixels
public static function getWidthPixels(string $text, string $font, int $font_size): int {
// https://www.php.net/manual/en/function.imageftbbox.php#refsect1-function.imageftbbox-returnvalues
$bbox = imageftbbox($font_size, 0, $font, " " . $text);
return $bbox[2] - $bbox[0];
}
// Returns wrapped format (with newlines) of a piece of text (meant to be rendered on an image)
// using the width of rendered bounding box of text
public static function wrapTextByPixels(
string $text,
int $line_max_pixels,
int $font_size,
string $font
): string {
$words = explode(' ', $text); // tokenize the text into words
$lines = []; // Array[Array[string]]: array to store lines of words
$crr_line_idx = 0; // (zero-based) index of current lines in which words are being added
$crr_line_pixels = 0; // width of current line (in which words are being added) in pixels
foreach ($words as $word) {
// determine the new width of current line (in pixels) if the current word is added to it (including space)
$crr_line_new_pixels = $crr_line_pixels + ImageTextRenderUtils::getWidthPixels(' ' . $word, $font, $font_size);
// determine the width of current word in pixels
$crr_word_pixels = ImageTextRenderUtils::getWidthPixels($word, $font, $font_size);
if ($crr_word_pixels > $line_max_pixels) {
// if the current word itself is too long to fit in single line
// then we have no option: it must still be put in oneline only
if ($crr_line_pixels == 0) {
// but it is put into current line only if current line is empty
$lines[$crr_line_idx] = array($word);
$crr_line_idx++;
} else {
// otherwise if current line is non-empty, then the extra long word is put into a newline
$crr_line_idx++;
$lines[$crr_line_idx] = array($word);
$crr_line_idx++;
$crr_line_pixels = 0;
}
} else if ($crr_line_new_pixels > $line_max_pixels) {
// otherwise if new width of current line (including current word and space)
// exceeds the maximum permissible width, then force the current word into newline
$crr_line_idx++;
$lines[$crr_line_idx] = array($word);
$crr_line_pixels = $crr_word_pixels;
} else {
// else if the current word (including space) can fit in the current line, then put it there
$lines[$crr_line_idx][] = $word;
$crr_line_pixels = $crr_line_new_pixels;
}
}
// after the above foreach loop terminates, the $lines 2-d array Array[Array[string]]
// would contain words segregated into lines to preserve the $line_max_pixels
// now we just need to stitch together lines (array of word strings) into a single continuous piece of text with
$concatenated_string = array_reduce(
$lines,
static function (string $wrapped_text, array $crr_line): string {
return $wrapped_text . PHP_EOL . implode(' ', $crr_line);
},
''
);
// the above process of concatenating lines into single piece of text will inadvertently
// add an extra newline '
' character in the beginning; so we must remove that
return StringUtils::removeFirstOccurrence($concatenated_string, "
");
}
相关文章