Error using return in php
Answer
When using mysqli_conn, as long as there is an "i" statement, an error will occur. I installed the latest version of php.
In a function, using return $db also causes an error.
What's going on?
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Both mysql and mysqli are connection extensions for MySQL For PHP. There are only two reasons for the error, 1: The mysqli extension is not installed at all; 2: Wrong parameter usage or wrong database information
What do you return? . If a function function a()
{
// The function is an independent world. There is no $db variable in the function at all. Where did you return it from?
return $db;
}
Copy code
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Because the foundation has not been laid.
Both mysql and mysqli are connection extensions for MySQL For PHP. There are only two reasons for the error, 1: The mysqli extension is not installed at all; 2: Wrong parameter usage or wrong database information
What do you return? . If a function function a()
{
// The function is an independent world. There is no $db variable in the function at all. Where did you return it from?
return $db;
}
Copy code
Other solutions
Well, I think the extension may not be turned on
Other solutions
Please send me the code
It’s very unclear to see like this
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Thank you! Mysqli is not open.
But the return still fails.
function db_connect()
{
@$db = mysqli_connect('localhost','root','8251617','bookmarks');
if (!$db)
{
throw new Exception('Could not connect to database server');
}
else
{
return $db;
echo 'dddd';
}
}
In the above code, if the return is removed, it will pass, but I need the return value.
}
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Thank you 1
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All operations after return will not continue
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The problem is: as long as there is a return in the code, an http 500 error will appear immediately, and the page cannot be found. It is the same error as the previous mysqli. Is there something that has not been opened?
Thank you
Other solutions
Have you installed Xdebug?
You can use it to track down similar errors in the future
Other solutions
There seems to be a problem with the code. .

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