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    <p>Actually I think it is not true: you can ovverride static propeties (<strong>you need >=5.3 PHP</strong> for that). But you have to be careful when refrencing for that static property (and this is the mistake in the original code)<br/> <br/> You need to use <strong>static::$myStaticProperty</strong> instead of using self::$myStaticProperty<br/> <br/> <strong>self::</strong> will refrence to the <strong>current class</strong> so if you are inside an inherited static method this will refrence the static property of that class defined that method! While using reference keyword static:: will act like $this - when you are using instance methods/propeties.<br/> <br/> doSomething() is an inherited static method in class Bar in your example. Since you used self:: there, it will reference to the static property of class Foo. This is the reason why you didn't see any difference... <strong>Try to change self:: to static::</strong>!<br/> <br/> Here is a code example - I used it myself to test those things. We have static property/method inheritance, override and value change in it - run it and you will see the result!<br/></p> <pre><code>class A { // a static property - we will test override with it protected static $var = 'class A var - override'; // a static property - we will test value overwrite with it protected static $var2 = 'class A var2 - value overwrite'; public static function myStaticOverridePropertyTest() { return static::$var; } public static function myStaticValueOverwritePropertyTest() { return static::$var2; } /** * This method is defined only here - class B will inherit this one! * We use it to test the difference btw self:: and static:: * * @return string */ public static function myStaticMethodTest() { //return self::getValue(); return static::getValue(); } /** * This method will be overwritten in class B * @return string */ protected static function getValue() { return 'value from class A'; } } class B extends A { // we override this inherited static property protected static $var = 'class B var - override'; /** * This method is overwritten from class A * @return string */ protected static function getValue() { return 'value from class B'; } /** * We modify the value of the inherited $var2 static property */ public static function modStaticProperty() { self::$var2 = 'class B - altered value! - value overwrite'; } } echo ("-- testing class A:\n"); echo (A::myStaticOverridePropertyTest(). "\n"); echo (A::myStaticValueOverwritePropertyTest(). "\n"); echo (A::myStaticMethodTest(). "\n"); echo ("-- now testing class B:\n"); echo (B::myStaticOverridePropertyTest(). "\n"); echo (B::myStaticValueOverwritePropertyTest(). "\n"); echo (" now invoking B::modStaticProperty() .\n"); B::modStaticProperty(); echo (B::myStaticValueOverwritePropertyTest(). "\n"); echo ("-- now re-testing class A:\n"); echo (A::myStaticOverridePropertyTest(). "\n"); echo (A::myStaticValueOverwritePropertyTest(). "\n"); echo (A::myStaticMethodTest(). "\n"); </code></pre> <p>This will output:<br/> <br/> -- testing class A:<br/> class A var - override<br/> class A var2 - value overwrite<br/> value from class A<br/> -- now testing class B:<br/> class B var - override<br/> class A var2 - value overwrite<br/> now invoking B::modStaticProperty() ...<br/> class B - altered value! - value overwrite<br/> -- now re-testing class A:<br/> class A var - override<br/> <strong>class B - altered value! - value overwrite</strong><br/> value from class A<br/> <br/> And here we are, you can see the difference between overriden and only value overwritten static properties... look the output line I marked with bold! When we invoked the modStaticProperty() of class B, it changed the value of that static variable in class A too. Since that static property was inherited and was not overriden! Think about it...</p>
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