IntNovAction.Utils.ExcelImporter 2.2.1

IntNovAction.Utils.ExcelImporter

Utility to import excel data into POCOs

The usage is quite simple:

// Define the destination POCO class
class SampleImportInto
{
    public int IntColumn { get; set; }
    public int? NullableIntColumn { get; set; }
    public decimal DecimalColumn { get; set; }
    public decimal? NullableDecimalColumn { get; set; }
    public float FloatColumn { get; set; }
    public float? NullableFloatColumn { get; set; }
    public string StringColumn { get; set; } 
    public DateTime DateColumn { get; set; }
    public DateTime? NullableDateColumn { get; set; }
    public bool BooleanColumn { get; set; }
    public bool? NullableBooleanColumn { get; set; }
}

// Read the excel file 
using (var stream = File.OpenRead("d:\ExcelWithData.xlsx"))
{
    // Create the typed importer
    var importer = new Importer<SampleImportInto>();

    // Configure
    importer
        .SetErrorStrategy(ErrorStrategy.AddElement)
        .FromExcel(stream, "Sheet Name")
        .For(p => p.IntColumn, "Int Column")
        .For(p => p.FloatColumn, "Float Column")
        .For(p => p.DecimalColumn, "Decimal Column")
        .For(p => p.NullableIntColumn, "Nullable Int Column")
        .For(p => p.NullableFloatColumn, "Nullable Float Column")
        .For(p => p.NullableDecimalColumn, "Nullable Decimal Column")
        .For(p => p.StringColumn, "String Column")
        .For(p => p.DateColumn, "Date Column")
        .For(p => p.NullableDateColumn, "Nullable Date Column")
        .For(p => p.BooleanColumn, "Boolean Column")
        .For(p => p.NullableBooleanColumn, "Nullable Boolean Column");

    // Import
    var importResults = importer.Import();
    
    // Read the imported objects...
    var numImportedItems = importResults.ImportedItems.Count();

    // Check the errors...
    var numImportedObjects = importResults.Errors.Count();
}

Error Handling

You can control how errors are handled during import using SetErrorStrategy:

• ErrorStrategy.AddElement: Adds the row even if it has errors.
• ErrorStrategy.DoNotAddElement: Skips rows with errors.

Nested Objects

Supports nested objects (1-1 relationships). The default constructor must create the nested objects:

class InnerClass { public int PropInt { get; set; } }
class ClassWithInnerClass {
    public InnerClass Inner { get; set; } = new InnerClass();
    public int TestInt { get; set; }
}

var importer = new Importer<ClassWithInnerClass>()
    .For(p => p.Inner.PropInt, "Inner Column")
    .For(p => p.TestInt, "Base Column");

Excel Template Generation

You can generate an Excel template for your import:

var importer = new Importer<SampleImportInto>()
    .For(p => p.IntColumn, "Int Column")
    .For(p => p.StringColumn, "String Column");

using (var excelStream = importer.GenerateExcel())
{
    // Save or send the template
}

With Sample Data

var sampleData = new List<SampleImportInto> { new SampleImportInto { IntColumn = 1, StringColumn = "Test" } };
using (var excelStream = importer.GenerateExcel(sampleData))
{
    // Save or send the template with sample rows
}

Duplicated Column Strategies

Control how duplicated columns are handled with SetDuplicatedColumnsStrategy:

• DuplicatedColumnStrategy.TakeFirst: Uses the first occurrence.
• DuplicatedColumnStrategy.TakeLast: Uses the last occurrence.
• DuplicatedColumnStrategy.RaiseError: Fails import if duplicates are found.

Custom row processing with CustomFor

You can execute custom logic for each imported row using CustomFor. This method receives a dictionary with the column values and the destination object, allowing you to process or validate data as needed:

using (var stream = File.OpenRead("d:\ExcelWithData.xlsx"))
{
    var importer = new Importer<SampleImportInto>()
        .FromExcel(stream, "Sheet Name")
        .For(p => p.IntColumn, "Int Column")
        .CustomFor((Dictionary<string, string> rowValues, SampleImportInto destination) =>
        {
            // Example: log or transform values
            Console.WriteLine($"Row IntColumn value: {rowValues["Int Column"]}");
            // You can also modify 'destination' here
        });

    var importResults = importer.Import();
}

You can combine CustomFor with duplicated column strategies:

importer
    .SetDuplicatedColumnsStrategy(DuplicatedColumnStrategy.TakeFirst) // or TakeLast, RaiseError
    .CustomFor((rowValues, destination) =>
    {
        // Will receive the value according to the selected strategy
        Console.WriteLine($"IntColumn: {rowValues["Int Column"]}");
    });

Row Index Mapping

You can map the Excel row index to a property in your POCO:

class SampleImportInto { public int RowIndex { get; set; } /* ... */ }

importer.SetRowIndex(p => p.RowIndex);

Supported Types

The importer supports the following property types:

• int, int?
• decimal, decimal?
• float, float?
• string
• DateTime, DateTime?
• bool, bool?

Dependencies & Compatibility

• Requires .NET Standard 2.0 or .NET Core 3.1.
• Uses ClosedXML for Excel file handling.