使用jquery解析html字符串

var html = '<div><h1>Hello World</h1><p>This is a paragraph</p></div>';
var elements = $.parseHTML(html);
console.log(elements);

[
    [
        "div",
        "<div><h1>Hello World</h1><p>This is a paragraph</p></div>"
    ],
    [
        "h1",
        "<h1>Hello World</h1>"
    ],
    [
        "p",
        "<p>This is a paragraph</p>"
    ]
]

var html = '<div><h1>Hello World</h1><p>This is a paragraph</p></div>';
var elements = $.grep(html, function(n) {
    return n.tagName.toLowerCase() === 'h1';
});
console.log(elements);

[
    [
        "h1",
        "<h1>Hello World</h1>"
    ]
]