rewriting core block issue

Question

I have trouble figuring out whats wrong with my rewrite. I have used the answer of this question as a reference.

I'm trying to rewrite the core block:

app\code\core\Mage\Adminhtml\Block\Sales\Order\Create\Header.php

Here's my module's config.xml:

<config>
<modules>
    <MyNameSpace_MyModule>
        <version>1.0.0</version>
    </MyNameSpace_MyModule>
</modules>

<global>
    <blocks>
        <Adminhtml>
            <rewrite>
                <Sales_Order_Create_Header>MyNameSpace_MyModule_Block_Header</Sales_Order_Create_Header> 
            </rewrite>
        </Adminhtml>
    </blocks>
</global>

This is the path to my block where i want to rewrite the function in Header.php:

app\code\local\MyNameSpace\MyModule\Block\Header.php

Content of Header.php:

<?php

class MyNameSpace_MyModule_Block_Header extends Mage_Adminhtml_Block_Sales_Order_Create_Header {
    //My rewrite
}

Answer 1

Try this code in your config.xml

<global>
    <blocks>
        <adminhtml>
            <rewrite>
                <sales_order_create_header>MyNameSpace_MyModule_Block_Header</sales_order_create_header> 
            </rewrite>
        </adminhtml>
    </blocks>
</global>