我有一个数据网格,我想使用各种(并非完美的)PHP 转换器/生成器将其导出为 RTF、PDF 等。
我最想念的是 HTML 表格根据单元格中字符串的长度自动调整列宽(字符串包含换行符,这让事情变得有点复杂,因为它们应该被保留)。
我需要一种算法,在给定单元格内容(纯文本)、表格的总宽度和字符的平均宽度的情况下,该算法将返回每列的宽度。如果已经有可用的东西,我不想重新发明轮子。
当然,如果字体是可变宽度的,它就不可能是完美的,但一个近似值就可以了。或者它可能有一个可配置的表格,其中包含每个字符的宽度。
如有任何提示,我们将不胜感激。
最佳答案
这不是一件容易的事。
在PHPExcel中,当单元格设置为自动宽度时,我们使用gd库imagettfbbox()函数
// font size should really be supplied in pixels in GD2,
// but since GD2 seems to assume 72dpi, pixels and points are the same
$fontFile = self::getTrueTypeFontFileFromFont($font);
$textBox = imagettfbbox($font->getSize(), $rotation, $fontFile, $text);
// Get corners positions
$lowerLeftCornerX = $textBox[0];
$lowerLeftCornerY = $textBox[1];
$lowerRightCornerX = $textBox[2];
$lowerRightCornerY = $textBox[3];
$upperRightCornerX = $textBox[4];
$upperRightCornerY = $textBox[5];
$upperLeftCornerX = $textBox[6];
$upperLeftCornerY = $textBox[7];
// Consider the rotation when calculating the width
$textWidth = max($lowerRightCornerX - $upperLeftCornerX, $upperRightCornerX - $lowerLeftCornerX);
return $textWidth;
虽然它非常密集,尤其是在处理大型工作表时,所以我们还有另一种(近似)方法
// Calculate column width in pixels. We assume fixed glyph width. Result varies with font name and size.
switch ($fontName) {
case 'Calibri':
// value 8.26 was found via interpolation by inspecting real Excel files with Calibri 11 font.
$columnWidth = (int) (8.26 * PHPExcel_Shared_String::CountCharacters($columnText));
$columnWidth = $columnWidth * $fontSize / 11; // extrapolate from font size
break;
case 'Arial':
// value 7 was found via interpolation by inspecting real Excel files with Arial 10 font.
$columnWidth = (int) (7 * PHPExcel_Shared_String::CountCharacters($columnText));
$columnWidth = $columnWidth * $fontSize / 10; // extrapolate from font size
break;
case 'Verdana':
// value 8 was found via interpolation by inspecting real Excel files with Verdana 10 font.
$columnWidth = (int) (8 * PHPExcel_Shared_String::CountCharacters($columnText));
$columnWidth = $columnWidth * $fontSize / 10; // extrapolate from font size
break;
default:
// just assume Calibri
$columnWidth = (int) (8.26 * PHPExcel_Shared_String::CountCharacters($columnText));
$columnWidth = $columnWidth * $fontSize / 11; // extrapolate from font size
break;
}
// Calculate approximate rotated column width
if ($rotation !== 0) {
if ($rotation == -165) {
// stacked text
$columnWidth = 4; // approximation
} else {
// rotated text
$columnWidth = $columnWidth * cos(deg2rad($rotation))
+ $fontSize * abs(sin(deg2rad($rotation))) / 5; // approximation
}
}
// pixel width is an integer
$columnWidth = (int) $columnWidth;
return $columnWidth;
关于php - 以类似 HTML 的方式计算列宽(基于单元格内容),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/3051809/