how to add field programmatically in Drupal 7 with dynamic content value? I have a function in my e-commerce website that allow users to create own stores, i need to add dynamic field (select list) contain the stores created by the logged user when he add new product to assign this product with store.

i try to add field on the content type 'product' but i found that drupal save the values in the database.
What is he best method that resolve my problem?
I'm not sure what you are trying to do. But if you are trying to add a new field programmatically, below is a code snippet that can get you started.

    $myField_name = "my_new_field_name";
    if(!field_info_field($myField_name)) // check if the field already exists.
    {
        $field = array(
            'field_name'    =&gt; $myField_name,
            'type'          =&gt; 'image',
        );
        field_create_field($field);

        $field_instance = array(
            'field_name'    =&gt; $myField_name,
            'entity_type'   =&gt; 'node',
            'bundle'        =&gt; 'CONTENT_TYPE_NAME',
            'label'         =&gt; t('Select an image'),
            'description'   =&gt; t(''),
            'widget'        =&gt; array(
                'type'      =&gt; 'image_image',
                'weight'    =&gt; 10,
            ),
            'formatter'     =&gt; array(
                'label'     =&gt; t('label'),
                'format'    =&gt; 'image'
            ),
            'settings'      =&gt; array(
                'file_directory'        =&gt; 'photos', // save inside "public://photos"
                'max_filesize'          =&gt; '4M',
                'preview_image_style'   =&gt; 'thumbnail',
                'title_field'           =&gt; TRUE,
                'alt_field'             =&gt; FALSE,
            )
        );
        field_create_instance($field_instance);
        drupal_set_message("Field created successfully!");
    }


Hope that works

Muhammad.