<form method="post" action="demo.php">
<input type="submit" name="foo" value="提交">
<input type="submit" name="bar" value="保存">
</form>

<form method="post" action="demo.php">
<button type="submit" name="foo" value="foo_value">提交</button>
<button type="submit" name="bar" value="bar_value">保存</button>
</form>