Php @ symbol usage introduction (error closing symbol)

Before the function, the error message is not displayed.
The preceding "@" can suppress the error, that is, it will not display the error, and then throw an exception to display the exception processing defined by itself. This is only added to prevent viewers from seeing the error, unfriendly pages cannot suppress errors, but can only Suppress display errors

Function foo ($ n)
{
$ Result = 1/$ n;
Return $ result;
}
Echo @ foo (0); // The function generates an error except 0, but this error is not displayed after @ is added.
Echo "end"; // output end
# Annotator

Same as //, # is a single line annotator (multiline Annotator is /**/).

 

Read a database tutorial instance

Function db_connect () // connect to the database
{
@ $ Db = mysql tutorial _ connect ('localhost', 'root', 'test ');
If (! $ Db)
Throw new Exception ('failed to connect to the database! Please try again! ');
Mysql_select_db ('book ');
Return $ db;
}