PHP - 如何在函数中使用SWITCH

Question

I am trying to cut down on the amount of select statements, updates etc in my code so I thought that I would try to create a function for this, however I am puzzled that my efforts are failing at the first hurdle.

I have Googled this issue quite comprehensively (I feel) and I can't find any differences in the examples that I have found.

This is my function complete with print statements to help me diagnose the issue.

function select_statement($action, $table, $where){
print $action.' - ';

switch ($action){
    case 'select':
        print 'select used - ';
        $thequery = 'SELECT * FROM '. $table . ' WHERE '. $where;
    case 'insert':
        print 'insert used - ';
        $thequery = 'INSERT INTO '. $table;
    case 'update':
        print 'update used - ';
        $thequery = 'UPDATE ' . $table . ' SET ';
    }
print $thequery;
mysql_query($thequery);

}

This is the line that calls the function:-

$logins = select_statement('select', 'users', 'user_id=1');//calls function

This is the result:-

select - select used - insert used - update used - UPDATE users SET 

As you can see the code is triggering each of the print statements and seemingly ignoring the 'case' statements.

I'm really not sure what it is that I am doing wrong here?

Answer 1

You forgot to use break. Without it each case statement will "fall through" to the next one and continue operating. break stops execution at the end of each case statement`;

switch ($action){
    case 'select':
        print 'select used - ';
        $thequery = 'SELECT * FROM '. $table . ' WHERE '. $where;
        break;
    case 'insert':
        print 'insert used - ';
        $thequery = 'INSERT INTO '. $table;
        break;
    case 'update':
        print 'update used - ';
        $thequery = 'UPDATE ' . $table . ' SET ';
        break;
    }