Question

我正在尝试使用LINQ to Excel并将列映射到对象属性，但我有一个非常奇怪的运行时错误，我无法理解导致它的原因。错误说明：

LinqToExcel.dll中出现未处理的“System.Data.DataException”类型异常

'oDateTime（-1.EDI_date'不是有效的列名。有效列名为：'EDI Date'，'Week No'，'Dist No＃'，'Cust Type' ，'Cust No＃'，'Site No＃'，'Date'，'Time'，'Card No＃'，'Reg'，'Bunker Sheet'，'Mileage'，

这很奇怪，因为我从未通过名称“oDateTime（-1.EDI_date”）引用任何列，似乎将Convert.ToDateTime函数解析为字符串或其他内容？

以下块是执行LINQ查询的函数：

public IEnumerable<EDI> getEDIs()
    {
        // Set date of last monday
        DateTime lastMonday = DateTime.Now.AddDays(-(int)DateTime.Now.DayOfWeek - 6);

        // Initialise Excel file
        var excelFile = new ExcelQueryFactory(DIRECTORY);

        // Create column mappings
        excelFile.AddMapping<EDI>(x => x.EDI_date, "EDI Date");
        excelFile.AddMapping<EDI>(x => x.Week_no, "Week No");
        excelFile.AddMapping<EDI>(x => x.Dist_no, "Dist No#");
        excelFile.AddMapping<EDI>(x => x.Cust_no, "Cust No#");
        excelFile.AddMapping<EDI>(x => x.Site_no, "Site No#");
        excelFile.AddMapping<EDI>(x => x.Card_no, "Card No#");
        excelFile.AddMapping<EDI>(x => x.Mileage, "Mileage");
        excelFile.AddMapping<EDI>(x => x.Quantity, "Quantity");
        excelFile.AddMapping<EDI>(x => x.Product_no, "Product No");
        excelFile.AddMapping<EDI>(x => x.Month_no, "Month No#");
        excelFile.AddMapping<EDI>(x => x.Month_week_no, "Week No#");
        excelFile.AddMapping<EDI>(x => x.Transaction_no, "Transaction No#");
        excelFile.AddMapping<EDI>(x => x.Band, "band");

        // Declare LINQ query
        IEnumerable<EDI> EDIs = from edi in excelFile.Worksheet<EDI>("EDI Data")
                   where DateTime.Compare(Convert.ToDateTime(edi.EDI_date) , lastMonday) <= 7
                   select edi;

        // Loop through results
        foreach (EDI edi in EDIs)
        {
            Console.WriteLine(edi.EDI_date);
        }

        return EDIs;
    }

现在，错误指向foreach循环，在“foreach”语句中是否相信...这是导致DataException的特定行：

>   foreach (EDI edi in EDIs)

另外，我班的代码：EDI如下，有2个构造函数

 class EDI
{
    public EDI(string edi_date, int week_no, int cust_no, int dist_no, int site_no, int card_no, int mileage, int quantity, int product_no, int month_no, int month_week_no, int transaction_no, int value, int band)
    {
        this.edi_date = edi_date;
        this.week_no = week_no;
        this.cust_no = cust_no;
        this.dist_no = dist_no;
        this.site_no = site_no;
        this.card_no = card_no;
        this.mileage = mileage;
        this.quantity = quantity;
        this.product_no = product_no;
        this.month_no = month_no;
        this.month_week_no = month_week_no;
        this.transaction_no = transaction_no;
        this.value = value;
        this.band = band;
    }

    public EDI()
    {
    }

    readonly string edi_date;
    public string EDI_date { get { return edi_date; } }

    readonly int week_no;
    public int Week_no { get { return week_no; } }

    readonly int dist_no;
    public int Dist_no { get { return dist_no; } }

    readonly int cust_no;
    public int Cust_no { get { return cust_no; } }

    readonly int site_no; 
    public int Site_no { get { return site_no; } }

    readonly int card_no;
    public int Card_no {get {return card_no;} }

    readonly int mileage;
    public int Mileage { get { return mileage; } }

    readonly int quantity;
    public int Quantity { get { return quantity; } }

    readonly int product_no;
    public int Product_no { get { return product_no; } }

    readonly int month_no;
    public int Month_no { get { return month_no; } }

    readonly int month_week_no;
    public int Month_week_no { get { return month_week_no; } }

    readonly int transaction_no;
    public int Transaction_no { get { return transaction_no; } }

    readonly int value;
    public int Value { get { return value; } }

    readonly int band;
    public int Band { get { return band; } }

}

为列名称获取“不是有效的列名”我没有提到，为什么？

0 个答案: