我想在网页中动态地包括一个脚本标签,但我无法控制它的src,所以src="source.js"可能看起来像这样。

document.write('<script type="text/javascript">')
document.write('alert("hello world")')
document.write('</script>')
document.write('<p>goodbye world</p>')

一般来说

<script type="text/javascript" src="source.js"></script>

在头部工作很好,但有没有其他方法,我可以动态添加source.js使用innerHTML之类的东西?

我已经试过了


当前回答

window.addEventListener("load", init); const loadScript = async (url) => { const response = await fetch(url); const script = await response.text(); eval(script); } function init() { const wistiaVideo = document.querySelector(".wistia_embed"); if ("IntersectionObserver" in window && "IntersectionObserverEntry" in window && "intersectionRatio" in window.IntersectionObserverEntry.prototype) { let lazyVideoObserver = new IntersectionObserver(function (entries, observer) { entries.forEach(function (entry) { if (entry.isIntersecting) { setTimeout(() => loadScript("//fast.wistia.com/assets/external/E-v1.js"), 1000); lazyVideoObserver.unobserve(entry.target); console.log("E-v1.js script loaded from fast.wistia.com"); } }); }); lazyVideoObserver.observe(wistiaVideo); } } <div style="height: 150vh; background-color: #f7f7f7;"></div> <h1>Wistia Video!</h1> <div class="wistia_embed wistia_async_29b0fbf547" style="width:640px;height:360px;">&nbsp;</div> <h1>Video Ended!</h1>

其他回答

我尝试递归地追加每个脚本

注意:如果你的脚本是一个接一个的,那么位置需要同步。

Major Dependency应该在数组的最后,以便初始脚本可以使用它

const scripts = ['https://www.gstatic.com/firebasejs/6.2.0/firebase-storage.js', 'https://www.gstatic.com/firebasejs/6.2.0/firebase-firestore.js', 'https://www.gstatic.com/firebasejs/6.2.0/firebase-app.js'] let count = 0 const recursivelyAddScript = (script, cb) => { const el = document.createElement('script') el.src = script if(count < scripts.length) { count ++ el.onload = recursivelyAddScript(scripts[count]) document.body.appendChild(el) } else { console.log('All script loaded') return } } recursivelyAddScript(scripts[count])

这是我的工作。

你可以检查一下。

var script_tag = document.createElement('script'); script_tag.setAttribute(“src”、“https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js”); document.head.appendChild (script_tag); 窗口。Onload = function() { if (window.jQuery) { //加载jQuery 警报(“在头部添加脚本标签!”); }其他{ //不加载jQuery 警告(“没有在头部添加脚本标签”); } }

一行代码(与上面的答案没有本质区别):

document.body.appendChild(document.createElement('script')).src = 'source.js';
var my_awesome_script = document.createElement('script');

my_awesome_script.setAttribute('src','http://example.com/site.js');

document.head.appendChild(my_awesome_script);

没有人提到它,但你也可以通过使用URL和Blob将实际的源代码插入到脚本标记中:

const jsCode = `
 // JS code in here. Maybe you extracted it from some HTML string.
`

const url = URL.createObjectURL(new Blob([jsCode]))
const script = document.createElement('script')
script.src = url
URL.revokeObjectURL(url) // dispose of it when done

至于jsCode,你可能已经从一些HTML中得到了它。

这里有一个更完整的例子,你如何处理HTML源代码中的任意数量的脚本:

main()

async function main() {
    const scriptTagOpen = /<script\b[^>]*>/g
    const scriptTagClose = /<\/script\b[^>]*>/g
    const scriptTagRegex = /<script\b[^>]*>[\s\S]*?<\/script\b[^>]*>/g

    const response = await fetch('path/to/some.html')
    const html = await response.text()

    someElement.innerHTML = html

    // We need to get the script tags and manually add them to DOM
    // because otherwise innerHTML will not execute them.
    const codes =
        html
            .match(scriptTagRegex)
            ?.map(code => code.replace(scriptTagOpen, '').replace(scriptTagClose, ''))
            .map(code => URL.createObjectURL(new Blob([code]))) || []

    for (const code of codes) {
        const script = document.createElement('script')
        script.src = code
        someElement.append(script)
        URL.revokeObjectURL(code)
    }
}