Add Search Bar in header

function add_search_to_wp_menu ( $items, $args ) {
if( 'primary' === $args -> theme_location ) {
$items .= '<li class="menu-item menu-item-search">';
$items .= '<form method="get" class="menu-search-form" action="' . get_bloginfo('home') . '/"><p><input class="text_input" type="text" value="Enter Text & Click to Search" name="s" id="s" onfocus="if (this.value == \'Enter Text & Click to Search\') {this.value = \'\';}" onblur="if (this.value == \'\') {this.value = \'Enter Text & Click to Search\';}" /><input type="submit" class="my-wp-search" id="searchsubmit" value="search" /></p></form>';
$items .= '</li>';
}
return $items;
}
add_filter('wp_nav_menu_items','add_search_to_wp_menu',10,2);