javascript - 下载 c# excel 字节数组并将其转换为 javascript blob

Question

我正在使用 POST 方法获取 Excel 文件的字节数组

C# 服务器端实现:

 downloadExcel() {
    ....
    FileResultDto fileResultDto = new FileResultDto
    {
       Data = ExcelHelper.CreateExcelFile(excelFile) //Data contains the byte array
    };

    return new JsonHttpResponseMessage(JsonConvert.SerializeObject(fileResultDto));
}

CreateExcelFile():

public byte[] CreateExcelFile(ExcelFile excelFile)
    {
        try
        {
            #region Validation

            if (excelFile == null)
            {
                throw new ArgumentNullException(nameof(excelFile));
            }

            #endregion

            byte[] bytes;

            using (ExcelPackage excelPackage = new ExcelPackage())
            {
                for (int i = 1; i <= excelFile.Worksheets.Count; i++)
                {
                    Worksheet worksheet = excelFile.Worksheets[i - 1];

                    excelPackage.Workbook.Worksheets.Add(worksheet.Name);

                    ExcelWorksheet currentExcelWorksheet = excelPackage.Workbook.Worksheets[i];

                    if (excelFile.HasLogoTemplate)
                    {
                        byte[] imageBytes = Convert.FromBase64String(LogoBase64);

                        Image image;
                        using (MemoryStream ms = new MemoryStream(imageBytes, 0, imageBytes.Length))
                        {
                            image = Image.FromStream(ms, true);
                        }

                        ExcelPicture picture = currentExcelWorksheet.Drawings.AddPicture("Logo", image);

                        picture.SetPosition(0, 4, 0, 10);

                        currentExcelWorksheet.Row(1).Height = 50;
                    }

                    SetColumnsWidths(currentExcelWorksheet, worksheet);

                    WriteHeaderRow(currentExcelWorksheet, worksheet.HeaderRow);

                    WriteCells(currentExcelWorksheet, worksheet.Cells);
                }

                #region Set Excel Stream

                bytes = excelPackage.GetAsByteArray();

                #endregion
            }

            return bytes;
        }
        catch (Exception exception)
        {
            throw new Exception("There was an error on excel export. Exception: ", exception);
        }
    }

前端实现:

public downloadExcel(): void {

    this.myRepository.downloadExcel(this.postData).then(result => {
        var byteArray = new Uint8Array(result.data.data);

        var a = window.document.createElement('a');
        a.href = window.URL.createObjectURL(new Blob([byteArray], { type: "application/octet-stream" }));

        a.download = "test.xlsx";

        document.body.appendChild(a);
        a.click();
        document.body.removeChild(a);
    }, error => {
        console.log(error);
    });
}

显然创建的 blob 文件似乎已损坏。有什么建议吗？问题出在哪里？

Answer 1

最终使用“arraybuffer”作为http请求的响应类型解决了问题。

let requestConfiguration: ng.IRequestConfig = {
        cache: ...,
        data: ...,
        headers: ...,
        method: ...,
        url: ...,
        responseType: 'arraybuffer'
    };        

    let promise: ng.IPromise<any> = this.$http(requestConfiguration);