使用LinqToCsv将CSV文件写入Sql数据库-.NET MVC 4-实体框架

Question

我正在尝试创建一个应用程序，用户可以在其中将.CSV文件上传到我创建的SQL数据库中。 当涉及到从视图中实际获取文件路径并将其写入数据库时​​，我有些困惑。

首先，这是我正在研究的模型：

    public class OutstandingCreditCsv
{
    [CsvColumn(FieldIndex = 1, CanBeNull = false)]
    public string PoNumber { get; set; }
    [CsvColumn(FieldIndex = 2, OutputFormat = "dd MMM HH:mm:ss")]
    public DateTime CreditInvoiceDate { get; set; }
    [CsvColumn(FieldIndex = 3)]
    public string CreditInvoiceNumber { get; set; }
    [CsvColumn(FieldIndex = 4, CanBeNull = false, OutputFormat = "C")]
    public decimal CreditInvoiceAmount { get; set; }
}

到目前为止，这是控制器代码：

        public ActionResult Index()
    {
        CsvFileDescription inputFileDescription = new CsvFileDescription
        {
            SeparatorChar = ',',
            FirstLineHasColumnNames = true
        };

        var context = new CsvContext();

        IEnumerable<OutstandingCreditCsv> csvList =
        context.Read<OutstandingCreditCsv>("C:/Users/BlahBlah/Desktop/CsvUploadTestFile.csv", inputFileDescription);

        foreach (OutstandingCreditCsv line in csvList)
        {

        }

        return View();
    }

我需要在两个方面提供一些指导。 我不确定如何将文件从视图传递到控制器，可以说我的视图很简单：

<form action="" method="POST" enctype="multipart/form-data">
<table style="margin-top: 150px;">
    <tr>
        <td>
            <label for="file">Filename:</label>
        </td>
        <td>
            <input type="file" name="file" id="file"/>
        </td>
        <td><input type="submit" value="Upload"/></td>
    </tr>
</table>
</form>

我也不确定如何将csv数据实际循环到数据库中。 您可以看到控制器中的foreach循环为空。 任何帮助，将不胜感激。 谢谢！

Answer 1

我正在编辑帖子，以回答我遗漏的部分问题。 您在这里所做的就是将csv文件上传到一个临时位置，将其读入一个对象，然后，如果需要，您可以从该临时位置中删除csv文件（未显示）。

[HttpPost]
public JsonResult UploadValidationTable(HttpPostedFileBase csvFile)
{
    CsvFileDescription inputFileDescription = new CsvFileDescription
    {
         SeparatorChar = ',',
         FirstLineHasColumnNames = true
    };

    var cc = new CsvContext();
    string filePath = uploadFile(csvFile.InputStream);
    var model = cc.Read<OutstandingCreditCsv>(filePath, inputFileDescription);

    //if your csv has several rows convert it to a list of your model
    //var model = cc.Read<List<OutstandingCreditCsv>>(filePath, inputFileDescription);
   //then you can loop through and do the same as below
   /*foreach(var row in model)
   {
        var invoice = row.CreditInvoiceNumber;
   }*/

    try
    {
        //do what you need here, like save items to database
        var invoice = model.CreditInvoiceNumber;

        var invoiceTable = yourContext.yourTable
            .FirstOrDefault(x => x.yourTableID == passedInId);

       invoiceTable.CreditInvoiceNumber = model.CreditInvoiceNumber;
       yourContext.SaveChanges();
    }
    catch(LINQtoCSVException ex)
    {

    }

    return Json(model, "text/json");
}

private string uploadFile(Stream serverFileStream)
{
    string directory = "~/Content/CSVUploads";

    bool directoryExists = System.IO.Directory.Exists(Server.MapPath(directory));

    if (!directoryExists)
    {
        System.IO.Directory.CreateDirectory(Server.MapPath(directory));
    }

    string targetFolder = Server.MapPath(directory);
    string filename = Path.Combine(targetFolder, Guid.NewGuid().ToString() + ".csv");

    try
    {
        int length = 256; //todo: replace with actual length
        int bytesRead = 0;
        Byte[] buffer = new Byte[length];

        // write the required bytes
        using (FileStream fs = new FileStream(filename, FileMode.Create))
        {
            do
            {
                bytesRead = serverFileStream.Read(buffer, 0, length);
                fs.Write(buffer, 0, bytesRead);
            }
            while (bytesRead == length);
        }

        serverFileStream.Dispose();
        return filename;
    }
    catch (Exception ex)
    {
        return string.Empty;
    }
}