C＃MemoryStream - 此流不支持超时[重复]

Question

这个问题在这里已有答案：

• Newtonsoft Json.net - how to serialize content of a stream? 1回答

我正在尝试动态创建一个csv文件并将流输出到浏览器。

这是我的api终点：

    [System.Web.Http.HttpGet]
    [System.Web.Http.Route("export-to-csv")]
    public FileStreamResult ExportDeposits([FromUri(Name = "")]DepositSearchParamsVM depositSearchParamsVM)
        {
            if (depositSearchParamsVM == null)
            {
                depositSearchParamsVM = new DepositSearchParamsVM();
            }
            var records = _DepositsService.SearchDeposits(depositSearchParamsVM);
            var result = _DepositsService.WriteCsvToMemory(records);
            var memoryStream = new MemoryStream(result);

            return new FileStreamResult(memoryStream, "text/csv") { FileDownloadName = "export.csv" };
    }

这是我的服务方法：

public byte[] WriteCsvToMemory(IEnumerable<DepositSummaryVM> records)
        {
            using (var stream = new MemoryStream())
            using (var reader = new StreamReader(stream))
            using (var writer = new StreamWriter(stream))
            using (var csv = new CsvWriter(writer))
            {
                csv.WriteRecords(records);
                writer.Flush();
                stream.Position = 0;
                var text = reader.ReadToEnd();

                return stream.ToArray();

}

    }

这是错误消息：

{“message”：“发生了错误。”，“exceptionMessage”：“从'System.IO.MemoryStream''的'ReadTimeout'获取值时出错。”， “exceptionType”：“Newtonsoft.Json.JsonSerializationException”， “stackTrace”：“Newtonsoft.Json.Serialization.DynamicValueProvider.GetValue（Object target）\ r \ n在Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.CalculatePropertyValues（JsonWriter writer，Object value，JsonContainerContract contract，JsonProperty member，JsonProperty property，JsonContract＆在Newtonsoft.Json.Serialization.JsonSerializerInternalWriter的Ne​​wtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject（JsonWriter writer，Object value，JsonObjectContract contract，JsonProperty member，JsonContainerContract collectionContract，JsonProperty containerProperty）\ r \ n中的memberContract，Object＆memberValue）\ r \ n .SerializeValue（JsonWriter writer，Object value，JsonContract valueContract，JsonProperty成员，JsonContainerContract containerContract，JsonProperty containerProperty）\ r \ n在Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject（JsonWriter writer，Object value，JsonObjectContract contract，JsonProperty member，JsonContainerCon） tract collectionContract，JsonProperty containerProperty）\ r \ n在Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue（JsonWriter writer，Object value，JsonContract valueContract，JsonProperty成员，JsonContainerContract containerContract，JsonProperty containerProperty）\ r \ n在Newtonsoft.Json.Serialization。 JsonSerializerInternalWriter.Serialize（JsonWriter jsonWriter，Object value，Type objectType）\ r \ n在Newtonsoft.Json.JsonSerializer.SerializeInternal（JsonWriter jsonWriter，Object value，Type objectType）\ r \ n在System.Net.Http.Formatting.BaseJsonMediaTypeFormatter。 WriteToStream（Type type，Object value，Stream writeStream，Encoding effectiveEncoding）\ r \ n在System.Net.Http.Formatting.JsonMediaTypeFormatter.WriteToStream（Type type，Object value，Stream writeStream，Encoding effectiveEncoding）\ r \ n在System。 System.Net.Http.Formatting中的Net.Http.Formatting.BaseJsonMediaTypeFormatter.WriteToStream（Type type，Object value，Stream writeStream，HttpContent content）\ r \ n .BaseJsonMediaTypeFormatter.WriteToStreamAsync（Type type，Object value，Stream writeStream，HttpContent content，TransportContext transportContext，CancellationToken cancellationToken）\ r \ n ---从抛出异常的上一个位置开始的堆栈跟踪结束--- \ r \ n在系统中System.Web.Http.Ott.HttpMessageHandlerAdapter.d__13.MoveNext(）上的System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification（任务任务）\ r \ n的.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess（任务任务）\ r \ n “，”innerException“：{”message“：”发生错误。“，”exceptionMessage“：”此流不支持超时。“，”exceptionType“：”System.InvalidOperationException“，”stackTrace“：”at System.IO.Stream.get_ReadTimeout（）\ r \ n在GetReadTimeout（Object）\ r \ n在Newtonsoft.Json.Serialization.DynamicValueProvider.GetValue（Object target）“}}

Answer 1

Api试图将MemoryStream序列化为json。所以，你会尝试改变ContentType;

    [System.Web.Http.HttpGet]
    [System.Web.Http.Route("export-to-csv")]
    public FileStreamResult ExportDeposits([FromUri(Name = "")]DepositSearchParamsVM depositSearchParamsVM)
    {
        if (depositSearchParamsVM == null)
        {
            depositSearchParamsVM = new DepositSearchParamsVM();
        }
        var records = _DepositsService.SearchDeposits(depositSearchParamsVM);
        var result = _DepositsService.WriteCsvToMemory(records);
        var memoryStream = new MemoryStream(result);
        Response.ContentType = new MediaTypeHeaderValue("application/octet-stream").ToString();// Content type
        return new FileStreamResult(memoryStream, "text/csv") { FileDownloadName = "export.csv" };
    }