我必须为支付网关使用两个外部脚本。

现在两者都放在index.html文件中。

但是,我不想在开头本身就加载这些文件。

只有在用户打开特定组件(使用路由器视图)时才需要支付网关。

有办法实现这个目标吗?

谢谢。


当前回答

如果你试图利用一个在JavaScript文件中定义的变量,而这个文件是异步加载的,你收到一个'undefined'错误,这很可能是因为脚本还没有完成加载。要解决这个问题,可以利用onload函数确保脚本在尝试访问变量之前已经完成加载。举个例子:

const script = document.createElement(...) // set attribute and so on...
script.onload = () => {
  // do something with some variables/functions/logic from the loaded script
}

其他回答

mounted() {
    if (document.getElementById('myScript')) { return }
    let src = 'your script source'
    let script = document.createElement('script')
    script.setAttribute('src', src)
    script.setAttribute('type', 'text/javascript')
    script.setAttribute('id', 'myScript')
    document.head.appendChild(script)
}


beforeDestroy() {
    let el = document.getElementById('myScript')
    if (el) { el.remove() }
}

您可以使用vue-loader并在它们自己的文件中编写组件(单文件组件)。这将允许您在组件的基础上包含脚本和css。

在Vue 3中,我使用mejiamanuel57回答,并附加了一个检查,以确保脚本标记尚未加载。

    mounted() {
        const scripts = [
            "js/script1.js",
            "js/script2.js"
        ];
        scripts.forEach(script => {
            let tag = document.head.querySelector(`[src="${ script }"`);
            if (!tag) {
                tag = document.createElement("script");
                tag.setAttribute("src", script);
                tag.setAttribute("type", 'text/javascript');
                document.head.appendChild(tag); 
            }
        });
    // ...

来自mejiamanuel57的答案很好,但我想添加几个适合我的技巧(我花了几个小时在上面)。首先,我需要使用“窗口”范围。此外,如果您需要访问“onload”函数内的任何Vue元素,则需要为“this”实例创建一个新变量。

<script>
import { mapActions } from "vuex";
export default {
  name: "Payment",
  methods: {
    ...mapActions(["aVueAction"])
  },
  created() {
    let paywayScript = document.createElement("script");
    let self = this;
    paywayScript.onload = () => {
      // call to Vuex action.
      self.aVueAction();
      // call to script function
      window.payway.aScriptFunction();
    };
    // paywayScript.async = true;
    paywayScript.setAttribute(
      "src",
      "https://api.payway.com.au/rest/v1/payway.js"
    );
    document.body.appendChild(paywayScript);
  }
};
</script>

我在Vue 2.6上使用它。这里有一个关于“let self = this;”在Javascript中如何工作的技巧的解释:

var that = this;在JavaScript中是什么意思?

最简单的解决方案是将脚本添加到vue-project的index.html文件中

index . html:

<!DOCTYPE html>
<html lang="en">
   <head>
      <meta charset="utf-8">
      <title>vue-webpack</title>
   </head>
   <body>
      <div id="app"></div>
      <!-- start Mixpanel --><script type="text/javascript">(function(c,a){if(!a.__SV){var b=window;try{var d,m,j,k=b.location,f=k.hash;d=function(a,b){return(m=a.match(RegExp(b+"=([^&]*)")))?m[1]:null};f&&d(f,"state")&&(j=JSON.parse(decodeURIComponent(d(f,"state"))),"mpeditor"===j.action&&(b.sessionStorage.setItem("_mpcehash",f),history.replaceState(j.desiredHash||"",c.title,k.pathname+k.search)))}catch(n){}var l,h;window.mixpanel=a;a._i=[];a.init=function(b,d,g){function c(b,i){var a=i.split(".");2==a.length&&(b=b[a[0]],i=a[1]);b[i]=function(){b.push([i].concat(Array.prototype.slice.call(arguments,
         0)))}}var e=a;"undefined"!==typeof g?e=a[g]=[]:g="mixpanel";e.people=e.people||[];e.toString=function(b){var a="mixpanel";"mixpanel"!==g&&(a+="."+g);b||(a+=" (stub)");return a};e.people.toString=function(){return e.toString(1)+".people (stub)"};l="disable time_event track track_pageview track_links track_forms track_with_groups add_group set_group remove_group register register_once alias unregister identify name_tag set_config reset opt_in_tracking opt_out_tracking has_opted_in_tracking has_opted_out_tracking clear_opt_in_out_tracking people.set people.set_once people.unset people.increment people.append people.union people.track_charge people.clear_charges people.delete_user people.remove".split(" ");
         for(h=0;h<l.length;h++)c(e,l[h]);var f="set set_once union unset remove delete".split(" ");e.get_group=function(){function a(c){b[c]=function(){call2_args=arguments;call2=[c].concat(Array.prototype.slice.call(call2_args,0));e.push([d,call2])}}for(var b={},d=["get_group"].concat(Array.prototype.slice.call(arguments,0)),c=0;c<f.length;c++)a(f[c]);return b};a._i.push([b,d,g])};a.__SV=1.2;b=c.createElement("script");b.type="text/javascript";b.async=!0;b.src="undefined"!==typeof MIXPANEL_CUSTOM_LIB_URL?
         MIXPANEL_CUSTOM_LIB_URL:"file:"===c.location.protocol&&"//cdn.mxpnl.com/libs/mixpanel-2-latest.min.js".match(/^\/\//)?"https://cdn.mxpnl.com/libs/mixpanel-2-latest.min.js":"//cdn.mxpnl.com/libs/mixpanel-2-latest.min.js";d=c.getElementsByTagName("script")[0];d.parentNode.insertBefore(b,d)}})(document,window.mixpanel||[]);
         mixpanel.init("xyz");
      </script><!-- end Mixpanel -->
      <script src="/dist/build.js"></script>
   </body>
</html>