Question

我是新手。

我的班级：

if(!class_exists('my_connections')) {
    class my_connections {

        /* --------------- CHECKS IF CONNECTION EXISTS */
        public function is_connection($member_id, $connection_id) {

        global $db;

        $sql = "SELECT * FROM `my_connections` WHERE `member_id` = '".$member_id."' AND `connection_id` = '".$connection_id."'";
        $result = @mysql_query($sql,$db); check_sql(mysql_error(), $sql, 0);

        //echo '<pre>'. $sql .'</pre>';

        if(mysql_num_rows($result) > 0) {

            echo "YES THEY ARE FRIENDS";
            //$return = true;

        } else {

            echo "NO THEY ARE NOT FRIENDS"; 
            //$return = false;
        }

        //return $return;

        //echo $return;
        } // EO method - is_connection


    } // EO class

} //EO if !class_exists

在此实例化：

$mc = new my_connections;

$test = $mc->is_connection('2154', '139');

echo $test;

它返回echo语句就好了，但是没有返回boolean，

例如：而不是

echo $test;

我想对方法进行检查：

像这样：

if ($test) {
  //do something
}

方法内的echo语句将替换为return true / false

Answer 1

修改您的代码，如下所示

if(!class_exists('my_connections')) {
    class my_connections {

        /* --------------- CHECKS IF CONNECTION EXISTS */
        public function is_connection($member_id, $connection_id) {

        global $db;

        $sql = "SELECT * FROM `my_connections` WHERE `member_id` = '".$member_id."' AND `connection_id` = '".$connection_id."'";
        $result = @mysql_query($sql,$db); check_sql(mysql_error(), $sql, 0);

        //echo '<pre>'. $sql .'</pre>';

        if(mysql_num_rows($result) > 0) {

           // echo "YES THEY ARE FRIENDS";
            return true;

        } else {

            //echo "NO THEY ARE NOT FRIENDS"; 
            return false;
        }

        //return $return;

        //echo $return;
        } // EO method - is_connection


    } // EO class

} //EO if !class_exists

Answer 2

修改了你的课程：

if(!class_exists('my_connections')) {
    class my_connections {

        /* --------------- CHECKS IF CONNECTION EXISTS */
        public function is_connection($member_id, $connection_id) {

            global $db;

            $sql = "SELECT * FROM `my_connections` WHERE `member_id` = '".$member_id."' AND `connection_id` = '".$connection_id."'";
            $result = @mysql_query($sql,$db); check_sql(mysql_error(), $sql, 0);

            if(mysql_num_rows($result) > 0) {
                echo "YES THEY ARE FRIENDS"; // message is echoed when you call this method
                return true; // your variable is set 
            } 
            else {
                echo "NO THEY ARE NOT FRIENDS"; 
                return false;
            }
        }
    } // EO class
} //EO if !class_exists

你的代码：

 $mc = new my_connections;

 $test = $mc->is_connection('2154', '139'); // will automatically echo something from the class and set $test to true or false

Answer 3

试试这个：

if(!class_exists('my_connections')) {
    class my_connections { 

        public function is_connection($member_id, $connection_id) {

        global $db;    
        $sql = "SELECT * FROM `my_connections` WHERE `member_id` = '".$member_id."' AND `connection_id` = '".$connection_id."'";
        $result = @mysql_query($sql,$db); check_sql(mysql_error(), $sql, 0);

        return mysql_num_rows($result) > 0 ;   
    }      
}

检查后：

if(is_connection($member_id, $connection_id)){
 // do something
}

PHP类返回echo但不返回bool

3 个答案: