在官方的plugin/hello.php

function hello_dolly_get_lyric() {
	/** These are the lyrics to Hello Dolly */
	$lyrics = "Hello, Dolly
Well, hello, Dolly
Dolly'll never go away again";

	// Here we split it into lines
	$lyrics = explode( "\n", $lyrics );

	// And then randomly choose a line
	return wptexturize( $lyrics[ mt_rand( 0, count( $lyrics ) - 1 ) ] );
}

// This just echoes the chosen line, we'll position it later
function hello_dolly() {
	$chosen = hello_dolly_get_lyric();
	echo "<p id='dolly'>$chosen</p>";
}

// Now we set that function up to execute when the admin_notices action is called
add_action( 'admin_notices', 'hello_dolly' );