本文實例講述了PHP字符串word末字符實現大小寫互換的方法。分享給大家供大家參考。具體實現方法如下：一、要求： 給出一個字符串如 “A journey of, a thousand 'miles' must can't /"begin/" with a single step.” ，通過 PHP 程序處理變成 “a journeY oF, A thousanD 'mileS' musT can'T "begiN" witH A singlE steP.”這里需要注意：1、每個單詞最后的字符如果是大寫就變成小寫，如果是小寫就變成大寫。 2、需要考慮類似 can't 這種形式的轉換。 3、標點符號（只考慮 , ' " . ;）不用變化。二、參考算法如下：復制代碼 代碼如下: php function convertLastChar($str) { $markArr = array(", ", "' ", "/" ", ". ", "; "); $ret = ""; for ($i = 0, $j = strlen($str); $i $i++) { if ($i $j - 2) { $afterStr = $str{$i + 1} . $str{$i + 2}; } else if ($i $j - 1) { $afterStr = $str{$i + 1} . " "; } if (in_array($afterStr, $markArr) || $i == $j - 1 || $str{$i + 1} == " ") { $ret .= strtoupper($str{$i}) === $str{$i} strtolower($str{$i}) : strtoupper($str{$i}); } else { $ret .= $str{$i}; } } return $ret; } 測試代碼如下： 復制代碼 代碼如下: php //test $str1 = "A journey of, a thousand 'miles' must can't /"begin/" with a single step."; $str2 = "A journey of, a thousand 'miles' must can't /"begin/" with a single step. "; $str3 = "A journey of, a thousand 'miles' must can't /"begin/" with a single step. a "; $str4 = "A journey of, a thousand 'miles' must can't /"begin/" with a single step. a B"; $str5 = "A journey of, a thousand 'miles' must can't /"begin/" with a single step. a b'"; $str6 = "A journey of, a thousand 'miles' must can't /"begin/" with a single step. a B/""; echo "source: br/ " . $str1 . " br/ result: br/ " . convertLastChar($str1) . " br/ br/ echo "source: br/ " . $str2 . " br/ result: br/ " . convertLastChar($str2) . " br/ br/ echo "source: br/ " . $str3 . " br/ result: br/ " . convertLastChar($str3) . " br/ br/ echo "source: br/ " . $str4 . " br/ result: br/ " . convertLastChar($str4) . " br/ br/ echo "source: br/ " . $str5 . " br/ result: br/ " . convertLastChar($str5) . " br/ br/ echo "source: br/ " . $str6 . " br/ result: br/ " . convertLastChar($str6) . " br/ br/ 運行結果如下： 復制代碼 代碼如下:source: A journey of, a thousand 'miles' must can't "begin" with a single step. result: a journeY oF, A thousanD 'mileS' musT can'T "begiN" witH A singlE steP.source: A journey of, a thousand 'miles' must can't "begin" with a single step. result: a journeY oF, A thousanD 'mileS' musT can'T "begiN" witH A singlE steP.source: A journey of, a thousand 'miles' must can't "begin" with a single step. a result: a journeY oF, A thousanD 'mileS' musT can'T "begiN" witH A singlE steP. Asource: A journey of, a thousand 'miles' must can't "begin" with a single step. a B result: a journeY oF, A thousanD 'mileS' musT can'T "begiN" witH A singlE steP. A bsource: A journey of, a thousand 'miles' must can't "begin" with a single step. a b' result: a journeY oF, A thousanD 'mileS' musT can'T "begiN" witH A singlE steP. A B'source: A journey of, a thousand 'miles' must can't "begin" with a single step. a B" result: a journeY oF, A thousanD 'mileS' musT can'T "begiN" witH A singlE steP. A b"希望本文所述對大家的PHP程序設計有所幫助。PHP教程
