PHP · Theory

vfprintf()

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Theory

273/352

vfprintf()

vfprintf() is simple if you keep it on paper. Amit uses it for Hello, Asha in a web page.

Keep vfprintf() small. Amit should finish Hello, Asha in a few lines, not a 40-line dump.

vfprintf() exists so Amit can keep Hello, Asha correct in a web page.

Amit ships vfprintf() in a web page. That is the use case worth saying.

Don’t do this with vfprintf() — missing semicolon. Interviewers spot it in ten seconds.

Place vfprintf() next to nearby PHP work — echo / print is the link.

Viva for vfprintf() — what it is → echo / print → the mistake (missing semicolon).

Exam tip

Say vfprintf() in one breath, then echo / print, then missing semicolon.

Example

<?php
// vfprintf()
$scores = [80, 90, 70];
$avg = array_sum($scores) / count($scores);
echo "avg=" . number_format($avg, 1) . "\n";
foreach ($scores as $s) {
  if ($s >= 80) echo "high: $s\n";
}

vfprintf(): scores array, print avg, then high marks. Say the output.

Short notes

Defvfprintf() — Amit uses it for Hello, Asha in a web page.
Rulevfprintf() → echo / print.
Remembervfprintf() + a .php page (a web page).
Usevfprintf() in a web page (Hello, Asha).
Trapvfprintf() — missing semicolon.
Exvfprintf() → Hello, Asha.

PHP · Theory

vfprintf()

← All stacks

Theory

273/352

vfprintf()

vfprintf() is simple if you keep it on paper. Amit uses it for Hello, Asha in a web page.

Keep vfprintf() small. Amit should finish Hello, Asha in a few lines, not a 40-line dump.

vfprintf() exists so Amit can keep Hello, Asha correct in a web page.

Amit ships vfprintf() in a web page. That is the use case worth saying.

Don’t do this with vfprintf() — missing semicolon. Interviewers spot it in ten seconds.

Place vfprintf() next to nearby PHP work — echo / print is the link.

Viva for vfprintf() — what it is → echo / print → the mistake (missing semicolon).

Exam tip

Say vfprintf() in one breath, then echo / print, then missing semicolon.

Example

<?php
// vfprintf()
$scores = [80, 90, 70];
$avg = array_sum($scores) / count($scores);
echo "avg=" . number_format($avg, 1) . "\n";
foreach ($scores as $s) {
  if ($s >= 80) echo "high: $s\n";
}

vfprintf(): scores array, print avg, then high marks. Say the output.

Short notes

Defvfprintf() — Amit uses it for Hello, Asha in a web page.
Rulevfprintf() → echo / print.
Remembervfprintf() + a .php page (a web page).
Usevfprintf() in a web page (Hello, Asha).
Trapvfprintf() — missing semicolon.
Exvfprintf() → Hello, Asha.

vfprintf()

Example

Short notes

Questions

vfprintf()

Example

Short notes

Questions