retrieve posted blog content in wordpress based on id or permalink

I hope somebody know the answer of my question.

How do I retrieve posted blog content in wordpress开发者_StackOverflow社区 based on id or permalink? I need the API.

Thank you

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Wordpress documentation is your friend: get_post

e.g:

<?php
$my_id = 7;
$post = get_post($my_id); 
$content = $post->post_content;
?>