Strings and Text

String Length

strlen counts the bytes in a simple string.

string length For plain ASCII text, `strlen` matches the visible character count.

String Length

name
string_length.php
Replay: real traced execution (multi-file project)
<?php
$name = "Ada";
$message = "Hello, " . $name;
$length = strlen($message);

echo "name=" . $name . "\n";
echo "message=" . $message . "\n";
echo "length=" . $length . "\n";

<?php
$name = "Grace";
$message = "Hello, " . $name;
$length = strlen($message);

echo "name=" . $name . "\n";
echo "message=" . $message . "\n";
echo "length=" . $length . "\n";

<?php
$name = "Linus";
$message = "Hello, " . $name;
$length = strlen($message);

echo "name=" . $name . "\n";
echo "message=" . $message . "\n";
echo "length=" . $length . "\n";

  1. $name ← Ada, $message ← Hello, Ada, $length ← 10

    1<?php2$name→ Ada = "Ada"; //@name="Grace", "Linus"3$message→ Hello, Ada = "Hello, " . $nameAda;4$length→ 10 = strlen($messageHello, Ada);56echo "name=" . $nameAda . "\n";7echo "message=" . $messageHello, Ada . "\n";8echo "length=" . $length10 . "\n";
    outputname=Ada
message=Hello, Ada
length=10

  1. $name ← Grace, $message ← Hello, Grace, $length ← 12

    1<?php2$name→ Grace = "Grace";3$message→ Hello, Grace = "Hello, " . $nameGrace;4$length→ 12 = strlen($messageHello, Grace);56echo "name=" . $nameGrace . "\n";7echo "message=" . $messageHello, Grace . "\n";8echo "length=" . $length12 . "\n";
    outputname=Grace
message=Hello, Grace
length=12

  1. $name ← Linus, $message ← Hello, Linus, $length ← 12

    1<?php2$name→ Linus = "Linus";3$message→ Hello, Linus = "Hello, " . $nameLinus;4$length→ 12 = strlen($messageHello, Linus);56echo "name=" . $nameLinus . "\n";7echo "message=" . $messageHello, Linus . "\n";8echo "length=" . $length12 . "\n";
    outputname=Linus
message=Hello, Linus
length=12