Question

在我的Ext Js解决方案中，我正在调用一个返回此JSON格式的服务

{"success":true,"filename":"spreadsheet.xlsx","file":[80,75,3,4,20,0,...(many more)]}

如何使用文件名和字节数组（文件）的内容创建文件下载对话框？

更新

所以我发现这一点开始下载

var a = window.document.createElement('a');
                    a.href = window.URL.createObjectURL(new Blob(data.file, { type: 'application/octet-stream' }));
                    a.download = data.filename;

                    // Append anchor to body.
                    document.body.appendChild(a)
                    a.click();

                    // Remove anchor from body
                    document.body.removeChild(a)

到目前为止很好

但我得到的文件已损坏，所以我怀疑我需要对文件变量进行编码/解码？

Answer 1

我必须先将文件转换为Uint8Array，然后再将其传递给Blob

var arr = data.file;
var byteArray = new Uint8Array(arr);
var a = window.document.createElement('a');

a.href = window.URL.createObjectURL(new Blob([byteArray], { type: 'application/octet-stream' }));
a.download = data.filename;

// Append anchor to body.
document.body.appendChild(a)
a.click();


// Remove anchor from body
document.body.removeChild(a)

阅读这个答案有很多帮助https://stackoverflow.com/a/16245768/1016439

Answer 2

Building on Jepzen's response, I was able to use this technique to download a document from AWS S3 from within the browser. +1 Jepzen

s3.getObject(params, function(err, data) {
      if (err === null) {
         var arr = data.Body;
         var byteArray = new Uint8Array(arr);
         var a = window.document.createElement('a');

         a.href = window.URL.createObjectURL(new Blob([byteArray], { type: 'application/octet-stream' }));
         a.download = fName; //fName was the file name portion of the key what was passed in as part of the key value within params. 

         // Append anchor to body.
         document.body.appendChild(a)
         a.click();

         // Remove anchor from body
         document.body.removeChild(a)
      } else {
        result = 'failure'
         console.log("Failed to retrieve an object: " + err);
      }
});

文件在javascript / Extjs中下载一个字节数组作为文件

2 个答案: