ExcelMapper Map Column Name With Different Property Name

When you are reading and writing excel files or communicating with databases or other table formats, sometimes, you will see that your property name is different from the column name.

So as an example let's consider the following excel file which contains books related data.

Now you can see that we have the following class defined to load the above data.

private class Book
{
    public int BookId { get; set; }
    public string Title { get; set; }
    public int NoOfPages { get; set; }
    public int AuthorId { get; set; }
}

Now the problem is that the BookId, NoOfPages, and AuthorId properties are not matching with columns defined in the excel file and you also don't want to change the property names to match the column names in the excel file.

To solve this issue, you can use the Column attributes and specified the column name as shown below.

private class Book
{
    [Column("Id")]
    public int BookId { get; set; }
    public string Title { get; set; }
    [Column("Pages")]
    public int NoOfPages { get; set; }
    [Column("AuthId")]
    public int AuthorId { get; set; }
}

In the above Book class, the BookId property is mapped to the Id column, the NoOfPages property is mapped to the Pages column and the AuthorId property is mapped to the AuthId column in the excel file.

The following example reads all the data and loads it to the list of Book objects.

public static void Example1()
{
    var excelMapper = new ExcelMapper(@"D:\myexcelfile.xlsx");
    var books = excelMapper.Fetch<Book>();

    foreach (var book in books)
    {
        Console.WriteLine("Id: {0}, Title: {1}, Pages: {2}, AuthorId: {3}", book.BookId, book.Title, book.NoOfPages, book.AuthorId);
    }
}

When you execute the above example, you will see the following output.

Id: 1, Title: Introduction to Machine Learning, Pages: 530, AuthorId: 1
Id: 2, Title: Advanced Topics in Machine Learning, Pages: 380, AuthorId: 1
Id: 3, Title: Introduction to Computing, Pages: 1171, AuthorId: 2
Id: 4, Title: Introduction to Microeconomics, Pages: 437, AuthorId: 2
Id: 5, Title: Calculus I, Pages: 1477, AuthorId: 3
Id: 6, Title: Calculus II, Pages: 1571, AuthorId: 3
Id: 7, Title: Trigonometry Basics, Pages: 540, AuthorId: 4
Id: 8, Title: Special Topics in Trigonometry, Pages: 490, AuthorId: 4
Id: 9, Title: Advanced Topics in Mathematics, Pages: 895, AuthorId: 4
Id: 10, Title: Introduction to AI, Pages: 530, AuthorId: 1