Strings and Text
Trim and Case
trim, strtoupper, and strtolower prepare text for display or comparison.
normalization
Text normalization changes formatting details such as whitespace or letter case.
Trim and Case
trim_and_case.php
Replay: real traced execution (multi-file project)
<?php
$raw = " Ada ";
$trimmed = trim($raw);
$upper = strtoupper($trimmed);
$lower = strtolower($trimmed);
echo "trimmed=" . $trimmed . "\n";
echo "upper=" . $upper . "\n";
echo "lower=" . $lower . "\n";
<?php
$raw = " Grace ";
$trimmed = trim($raw);
$upper = strtoupper($trimmed);
$lower = strtolower($trimmed);
echo "trimmed=" . $trimmed . "\n";
echo "upper=" . $upper . "\n";
echo "lower=" . $lower . "\n";
<?php
$raw = " Linus ";
$trimmed = trim($raw);
$upper = strtoupper($trimmed);
$lower = strtolower($trimmed);
echo "trimmed=" . $trimmed . "\n";
echo "upper=" . $upper . "\n";
echo "lower=" . $lower . "\n";
$raw ← Ada , $trimmed ← Ada, $upper ← ADA, $lower ← ada
1<?php2$raw→ Ada = " Ada "; //@raw=" Grace ", " Linus "3$trimmed→ Ada = trim($raw Ada );4$upper→ ADA = strtoupper($trimmedAda);5$lower→ ada = strtolower($trimmedAda);67echo "trimmed=" . $trimmedAda . "\n";8echo "upper=" . $upperADA . "\n";9echo "lower=" . $lowerada . "\n";outputtrimmed=Ada upper=ADA lower=ada
$raw ← Grace , $trimmed ← Grace, $upper ← GRACE, $lower ← grace
1<?php2$raw→ Grace = " Grace ";3$trimmed→ Grace = trim($raw Grace );4$upper→ GRACE = strtoupper($trimmedGrace);5$lower→ grace = strtolower($trimmedGrace);67echo "trimmed=" . $trimmedGrace . "\n";8echo "upper=" . $upperGRACE . "\n";9echo "lower=" . $lowergrace . "\n";outputtrimmed=Grace upper=GRACE lower=grace
$raw ← Linus , $trimmed ← Linus, $upper ← LINUS, $lower ← linus
1<?php2$raw→ Linus = " Linus ";3$trimmed→ Linus = trim($raw Linus );4$upper→ LINUS = strtoupper($trimmedLinus);5$lower→ linus = strtolower($trimmedLinus);67echo "trimmed=" . $trimmedLinus . "\n";8echo "upper=" . $upperLINUS . "\n";9echo "lower=" . $lowerlinus . "\n";outputtrimmed=Linus upper=LINUS lower=linus