首先将类名放入变量中:

$classname=$var.'Class';

$bar=new $classname("xyz");

看见 Namespaces and dynamic language features

如果使用命名空间

namespace com\company\lib;
class MyClass {
}

namespace com\company\lib;

//Works fine
$i = new MyClass();

$cname = 'MyClass';

//Errors
//$i = new $cname;

//Works fine
$cname = "com\\company\\lib\\".$cname;
$i = new $cname;

$reflectionClass = new ReflectionClass($className);

$module = $reflectionClass->newInstanceArgs($arrayOfConstructorParameters);

More information on dynamic classes and parameters

PHP>= 5.6

Argument Unpacking :

// The "..." is part of the language and indicates an argument array to unpack.
$module = new $className(...$arrayOfConstructorParameters);

感谢DisgruntledGoat指出这一点。

class Test {
    public function yo() {
        return 'yoes';
    }
}

$var = 'Test';

$obj = new $var();
echo $obj->yo(); //yoes

call_user_func() 或 call_user_func_array php方法。 你可以在这里查看( call_user_func_array , call_user_func ).

例子

class Foo {
static public function test() {
    print "Hello world!\n";
}
}

 call_user_func('Foo::test');//FOO is the class, test is the method both separated by ::
 //or
 call_user_func(array('Foo', 'test'));//alternatively you can pass the class and method as an array

如果你有要传递给方法的参数,那么使用 call_user_func_array() 功能。

class foo {
function bar($arg, $arg2) {
    echo __METHOD__, " got $arg and $arg2\n";
}
}

// Call the $foo->bar() method with 2 arguments
call_user_func_array(array("foo", "bar"), array("three", "four"));
//or
//FOO is the class, bar is the method both separated by ::
call_user_func_array("foo::bar"), array("three", "four"));