AJAX 调用 WebAPI Get 方法的参数不下载文件 ASP .NET MVC

Posted 2023-04-13

【中文标题】AJAX 调用 WebAPI Get 方法的参数不下载文件 ASP .NET MVC

【英文标题】：AJAX call to WebAPI Get method with Parameters not downloading file ASP .NET MVC

【发布时间】：2020-04-07 06:31:14

【问题描述】：

我正在尝试从 WEB API Get 类型的 HttpResponseMessage 方法下载一个 excel 文件。 我可以通过 AJAX 调用来访问该方法，该方法还返回一个结果内容，但它没有在浏览器上下载文件。我试过window.location，它重定向到一个新页面，上面写着-'该网站无法显示该页面'。我尝试通过在成功和错误中发出警报来进行调试，它在错误中作为 [Object object] 发出警报。以下是我的代码，请纠正我哪里出错了。谢谢。

javascript

$(document).ready(function () 
    $("#btnDownload").click(function ()         
        var apiUrl = "../api/DownloadExcel/ExportExcelFile?OriginalRequestNumber=";
        var originalReqIdentifier = $('#OriginalRequestNumber').val();
        $.ajax(
            url: apiUrl + originalReqIdentifier,
            type: 'GET',
            dataType: 'json',
            success: function (data) 
                alert(data);
            ,
            error: function (data) 
                alert('hi');
            
        );
    );
);

html

<input href="#" class="btn" type="Submit" id="btnDownload" name="btnDownload" value="Download" />

c#

    public class DownloadExcelController : ApiController

    private IExcelExport _excelExport  get; set; 

    public DownloadExcelController()
    
        _excelExport = new GenerateExcel();
    
// GET api/DownloadExcel/ExportExcelFile
    [HttpGet]       
    public HttpResponseMessage ExportExcelFile(string OriginalRequestNumber)
    
        var ObjectToExcel = new List<DummyExternalLoginViewModel>
        
            new DummyExternalLoginViewModel  Name = "Mohammed", FamilyName= "Ansari", State = "CA",
            new DummyExternalLoginViewModel  Name = "Harvey", FamilyName= "Spectre", State = "NY",
            new DummyExternalLoginViewModel  Name = "Mike", FamilyName= "Ross", State = "NY",
            new DummyExternalLoginViewModel  Name = "Donald", FamilyName= "Trump", State = "AL",
            new DummyExternalLoginViewModel  Name = "Spencer", FamilyName= "Mike", State = "AK",
            new DummyExternalLoginViewModel  Name = "Trump", FamilyName= "Donald", State = "AZ",
            new DummyExternalLoginViewModel  Name = "Bill", FamilyName= "Gates", State = "AR"
        ;
        var resultContent = _excelExport.Export(ObjectToExcel, "ExcelExport", true);

        return resultContent;
      
 

【参考方案1】：

您在双方都有问题 - 客户端和服务器问题：

使用同步文件下载（或如Download a file by jQuery.Ajax 所述的异步）：

$(document).ready(function () 
    $("#btnDownload").click(function ()         
        var apiUrl = "../api/DownloadExcel/ExportExcelFile?OriginalRequestNumber=";
        var originalReqIdentifier = $('#OriginalRequestNumber').val();

        window.location = apiUrl + originalReqIdentifier;
    );
);

定义HttpResponseMessage所需的属性：

[HttpGet]       
public HttpResponseMessage ExportExcelFile(string OriginalRequestNumber)

    // ..
    var resultContent = _excelExport.Export(ObjectToExcel, "ExcelExport", true);

    var stream = new MemoryStream(resultContent);

    var response = new HttpResponseMessage(HttpStatusCode.OK)  Content = new StreamContent(stream) ;

    response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")  FileName = "file.xlsx" ;
    response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/vnd.ms-excel");

    return response;
 

【讨论】：

这些响应行已在 Export 方法中定义。新窗口打开时出现错误 - 此错误（HTTP 405 Method Not Allowed）表示 Internet Explorer 能够连接到该网站，但该网站存在编程错误。

请在浏览器检查时查看附加的错误图像

【参考方案2】：

<script>
$(document).ready(function () 
    $("#btnDownload").click(function ()         
        var apiUrl = "../api/DownloadExcel/ExportExcelFile?OriginalRequestNumber=";
        var originalReqIdentifier = $('#OriginalRequestNumber').val();          
        $.ajax(
            url: apiUrl + originalReqIdentifier,
            type: 'GET',
            dataType: 'json',
            success: function (data) 
                alert(data);
            ,
            error: function (data) 
                window.location = apiUrl + originalReqIdentifier;
            
        );
    );
);
</script>

放置 window.location = apiUrl + originalReqIdentifier;在 Ajax 错误中，为我工作。