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42 lines
589 B
Markdown
42 lines
589 B
Markdown
# PossiblyUndefinedArrayOffset
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Emitted when trying to access a possibly undefined array offset
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```php
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<?php
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if (rand(0, 1)) {
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$arr = ["a" => 1, "b" => 2];
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} else {
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$arr = ["a" => 3];
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}
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echo $arr["b"];
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```
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## How to fix
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You can use the null coalesce operator to provide a default value in the event the array offset does not exist:
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```php
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<?php
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...
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echo $arr["b"] ?? 0;
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```
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Alternatively, you can ensure that the array offset always exists:
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```php
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<?php
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if (rand(0, 1)) {
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$arr = ["a" => 1, "b" => 2];
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} else {
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$arr = ["a" => 3, "b" => 0];
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}
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echo $arr["b"];
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```
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