Javascript 无法读取属性';创建承诺能力';未定义的

Javascript 无法读取属性';创建承诺能力';未定义的,javascript,angular,amd,systemjs,pdfjs,Javascript,Angular,Amd,Systemjs,Pdfjs,我试图在一个Angular项目中使用ngx extended pdf viewer,该项目使用amd.min.js作为依赖项。如果我删除amd作为一个依赖它的工作良好。但遗憾的是,我不能删除它,因为很多其他事情都依赖于它 这是可复制的html <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta http

我试图在一个Angular项目中使用
ngx extended pdf viewer
,该项目使用
amd.min.js
作为依赖项。如果我删除amd作为一个依赖它的工作良好。但遗憾的是,我不能删除它,因为很多其他事情都依赖于它

这是可复制的html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Hi Duniya</title>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/4.0.0/system.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/4.0.0/extras/amd.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/4.0.0/extras/named-exports.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/4.0.0/extras/named-register.min.js"></script>
    <script src="https://unpkg.com/ngx-extended-pdf-viewer@9.0.0-alpha.5/assets/pdf.worker-2.7.684.js"></script>
    <script src="https://unpkg.com/ngx-extended-pdf-viewer@9.0.0-alpha.5/assets/pdf-2.7.684.js"></script>
    <script src="https://unpkg.com/ngx-extended-pdf-viewer@9.0.0-alpha.5/assets/viewer-2.7.684.js"></script>    
</head>
<body>
    hello
</body>
</html>

你好,杜妮娅
你好

在amd之前加载所有三个pdf模块

    <script src="https://unpkg.com/ngx-extended-pdf-viewer@9.0.0-alpha.5/assets/pdf.worker-2.7.684.js"></script>
    <script src="https://unpkg.com/ngx-extended-pdf-viewer@9.0.0-alpha.5/assets/pdf-2.7.684.js"></script>
    <script src="https://unpkg.com/ngx-extended-pdf-viewer@9.0.0-alpha.5/assets/viewer-2.7.684.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/4.0.0/system.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/4.0.0/extras/amd.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/4.0.0/extras/named-exports.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/4.0.0/extras/named-register.min.js"></script>
如果在
amd
之前加载
pdf.js
,将执行以下行,从而使
pdf
模块在窗口对象中可用(根是窗口)

上面提到的代码片段来自

else if(typeof define === 'function' && define.amd)
    define("pdfjs-dist/build/pdf", [], factory);
root["pdfjs-dist/build/pdf"] = root.pdfjsLib = factory();