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array_diff_key()

Theory

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array_diff_key()

If you can teach array_diff_key() (function) using Meera walking through array_diff_key function, you know it. If you only know the heading, you don’t.

Do array_diff_key() (function) once by hand. one array_diff_key function step Meera can write from memory. Change one input. Say the new result out loud.

Skip array_diff_key() (function) and skipping the failure case for array_diff_key function shows up in a small live site.

array_diff_key() (function) shows up in a small live site. Name Meera walking through array_diff_key function, not “a real-world scenario”.

array_diff_key() (function) trap: skipping the failure case for array_diff_key function. Meera loses marks for that every viva.

Place array_diff_key() (function) next to nearby PHP work — one array_diff_key function step Meera can write from memory is the link.

Close array_diff_key() (function) with: “If I skip it, Meera walking through array_diff_key function goes wrong like this: skipping the failure case for array_diff_key function.”

Exam tip

Board: Meera walking through array_diff_key function. Dry-run array_diff_key() (function). Name the trap: skipping the failure case for array_diff_key function.

Example

<?php
// array_diff_key()
$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";
}

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

Short notes

Defarray_diff_key() (function) — Meera uses it for Meera walking through array_diff_key function in a small live site.
Rulearray_diff_key() (function) → one array_diff_key function step Meera can write from memory.
Rememberarray_diff_key() (function) + the PHP runtime (a small live site).
Usearray_diff_key() (function) in a small live site (Meera walking through array_diff_key function).
Traparray_diff_key() (function) — skipping the failure case for array_diff_key function.
Exarray_diff_key() (function) → Meera walking through array_diff_key function.

<?php // array_diff_key() $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"; }

array_diff_key()

Example

Short notes

Questions

array_diff_key()

Example

Short notes

Questions