使用javascript下载时,PDF为空白

我有一个Web服务,在其响应中返回PDF文件内容.我想在用户点击链接时将其下载为pdf文件.我在UI中编写的javascript代码如下:

$http.get('http://MyPdfFileAPIstreamURl').then(function(response){
var blob=new File([response],'myBill.pdf',{type: "text/pdf"});
var link=document.createElement('a');
link.href=window.URL.createObjectURL(blob);
link.download="myBill.pdf";
link.click();
});

'response'包含来自'MyPdfFileAPIstreamURl'的servlet输出流的PDF字节数组.并且流也未加密.

因此,当我点击链接时,PDF文件成功下载大小约为200KB.但是当我打开这个文件时,它会打开空白页面.下载的pdf文件的起始内容位于图像中.

我无法理解这里有什么问题.救命 !

这是下载的pdf文件的起始内容:

通过XMLHttpRequest和xhr.responseType = 'arraybuffer'; 代码解决了它:

var xhr = new XMLHttpRequest();
    xhr.open('GET', './api/exportdoc/report_'+id, true);
    xhr.responseType = 'arraybuffer';
    xhr.onload = function(e) {
       if (this.status == 200) {
          var blob=new Blob([this.response], {type:"application/pdf"});
          var link=document.createElement('a');
          link.href=window.URL.createObjectURL(blob);
          link.download="Report_"+new Date()+".pdf";
          link.click();
       }
    };
xhr.send();

我从服务器获取数据作为字符串(base64编码为字符串),然后在客户端我将其解码为base64,然后解码到数组缓冲区.

示例代码

function solution1(base64Data) {

    var arrBuffer = base64ToArrayBuffer(base64Data);

    // It is necessary to create a new blob object with mime-type explicitly set
    // otherwise only Chrome works like it should
    var newBlob = new Blob([arrBuffer], { type: "application/pdf" });

    // IE doesn't allow using a blob object directly as link href
    // instead it is necessary to use msSaveOrOpenBlob
    if (window.navigator && window.navigator.msSaveOrOpenBlob) {
        window.navigator.msSaveOrOpenBlob(newBlob);
        return;
    }

    // For other browsers: 
    // Create a link pointing to the ObjectURL containing the blob.
    var data = window.URL.createObjectURL(newBlob);

    var link = document.createElement('a');
    document.body.appendChild(link); //required in FF, optional for Chrome
    link.href = data;
    link.download = "file.pdf";
    link.click();
    window.URL.revokeObjectURL(data);
    link.remove();
}

function base64ToArrayBuffer(data) {
    var binaryString = window.atob(data);
    var binaryLen = binaryString.length;
    var bytes = new Uint8Array(binaryLen);
    for (var i = 0; i < binaryLen; i++) {
        var ascii = binaryString.charCodeAt(i);
        bytes[i] = ascii;
    }
    return bytes;
};