Solution:Step 1: Understand JSON key uniquenessJSON keys must be unique; if duplicates exist, last key overwrites previous.Step 2: Decode JSON with duplicate keysWhen decoded, the last 'a' key with value 3 overwrites the first 'a' key with value 1.Final Answer:Array with 'a' => 3 and 'b' => 2 becaus

[Solved] Given this PHP code:$json = '{"a":1,"b":2,"a":3}';$arr = json_decode($json, true);print_r($arr);What will be the output and why? | PHP

PHP - File Handling

Given this PHP code:

$json = '{"a":1,"b":2,"a":3}';
$arr = json_decode($json, true);
print_r($arr);

What will be the output and why?

AArray with 'a' => 3 and 'b' => 2 because last duplicate key wins

BArray with 'a' => 1 and 'b' => 2 because first key is kept

CError due to duplicate keys in JSON

DArray with both 'a' keys as separate entries

Step-by-Step Solution

Solution:

Step 1: Understand JSON key uniqueness
JSON keys must be unique; if duplicates exist, last key overwrites previous.
Step 2: Decode JSON with duplicate keys
When decoded, the last 'a' key with value 3 overwrites the first 'a' key with value 1.
Final Answer:
Array with 'a' => 3 and 'b' => 2 because last duplicate key wins -> Option A
Quick Check:
Duplicate JSON keys last wins [OK]

Quick Trick: Duplicate JSON keys overwrite earlier ones, last wins [OK]

Common Mistakes:

Expecting error on duplicate keys
Thinking both keys are kept

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Given this PHP code:

Step 1: Understand JSON key uniqueness

Step 2: Decode JSON with duplicate keys

Final Answer:

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