What does @ mean before a variable? [duplicate]

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Reference - What does this symbol mean in PHP?

I have this assignment:

$buffer=@data_value[$i];

what does the @ mean?

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That prevents any warnings or errors from being thrown when accessing the ith element of data_value.

See this post for details.

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The @ will suppress errors about variable not being initialized (will evaluate as null instead).

Also, your code is probably missing a $ after @:

$buffer=@$data_value[$i];

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It is called the "error-control operator". Since it's an assignment, I believe you should do the rest yourself.

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As above, it suppresses the error if the array key doesn't exist. A version which will do the same without resorting to dodgy error suppression is

$buffer = array_key_exists($i, $data_value) ? $data_value[$i] : null;

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the @ in front of a statement means that no warnings/errors should be reported from the result of that statement. To put simply, Error Reporting is suppressed for this statement.

This is particularly useful, when e.g. @fclose(fopen("file.txt",w")) which can throw several warnings/errors depending on the situation, but with an @ in front of it, all these warnings or errors will be suppressed.