Add typed and DataTable import options for Excel

Examples/Excel/Import/Example-ImportDataTable.ps1

@@ -0,0 +1,13 @@
+Import-Module ../../PSWriteOffice.psd1 -Force
+
+$path = "$PSScriptRoot/DataTable.xlsx"
+$workbook = New-OfficeExcel
+$sheet = New-OfficeExcelWorkSheet -Workbook $workbook -WorksheetName 'Data' -Option Replace
+New-OfficeExcelValue -Worksheet $sheet -Row 1 -Column 1 -Value 'Name'
+New-OfficeExcelValue -Worksheet $sheet -Row 1 -Column 2 -Value 'Age'
+New-OfficeExcelValue -Worksheet $sheet -Row 2 -Column 1 -Value 'Jane'
+New-OfficeExcelValue -Worksheet $sheet -Row 2 -Column 2 -Value 31
+Save-OfficeExcel -Workbook $workbook -FilePath $path
+
+$table = Import-OfficeExcel -FilePath $path -AsDataTable
+$table | Format-Table

Examples/Excel/Import/Example-ImportTyped.ps1

@@ -0,0 +1,18 @@
+Import-Module ../../PSWriteOffice.psd1 -Force
+
+class Person {
+    [string]$Name
+    [int]$Age
+}
+
+$path = "$PSScriptRoot/Typed.xlsx"
+$workbook = New-OfficeExcel
+$sheet = New-OfficeExcelWorkSheet -Workbook $workbook -WorksheetName 'Data' -Option Replace
+New-OfficeExcelValue -Worksheet $sheet -Row 1 -Column 1 -Value 'Name'
+New-OfficeExcelValue -Worksheet $sheet -Row 1 -Column 2 -Value 'Age'
+New-OfficeExcelValue -Worksheet $sheet -Row 2 -Column 1 -Value 'John'
+New-OfficeExcelValue -Worksheet $sheet -Row 2 -Column 2 -Value 30
+Save-OfficeExcel -Workbook $workbook -FilePath $path
+
+$rows = Import-OfficeExcel -FilePath $path -Type ([Person])
+$rows | Format-Table

Sources/PSWriteOffice/Cmdlets/Excel/ImportOfficeExcelCommand.cs

@@ -42,22 +42,34 @@ public class ImportOfficeExcelCommand : PSCmdlet
     [Parameter]
     public SwitchParameter NoHeader { get; set; }
 
+    [Parameter]
+    public Type? Type { get; set; }
+
+    [Parameter]
+    public SwitchParameter AsDataTable { get; set; }
+
     protected override void ProcessRecord()
     {
         try
         {
-            var data = ExcelDocumentService.ImportWorkbook(FilePath, WorkSheetName, Culture, StartRow, EndRow, StartColumn, EndColumn, HeaderRow, NoHeader);
-            if (WorkSheetName != null && WorkSheetName.Length == 1 && data.TryGetValue(WorkSheetName[0], out var single))
+            var raw = ExcelDocumentService.ImportWorkbook(FilePath, WorkSheetName, Culture, StartRow, EndRow, StartColumn, EndColumn, HeaderRow, NoHeader);
+            var converted = new Dictionary<string, object>();
+            foreach (var kvp in raw)
+            {
+                converted[kvp.Key] = ExcelDocumentService.ConvertWorksheetData(kvp.Value, Type, AsDataTable);
+            }
+
+            if (WorkSheetName != null && WorkSheetName.Length == 1 && converted.TryGetValue(WorkSheetName[0], out var single))
             {
-                WriteObject(single, true);
+                WriteObject(single, !AsDataTable.IsPresent);
             }
-            else if ((WorkSheetName == null || WorkSheetName.Length == 0) && data.Count == 1)
+            else if ((WorkSheetName == null || WorkSheetName.Length == 0) && converted.Count == 1)
             {
-                WriteObject(data.Values.First(), true);
+                WriteObject(converted.Values.First(), !AsDataTable.IsPresent);
             }
             else
             {
-                WriteObject(data);
+                WriteObject(converted);
             }
         }
         catch (FileNotFoundException ex)

Sources/PSWriteOffice/Services/Excel/ExcelDocumentService.Worksheet.Data.cs

@@ -1,6 +1,8 @@
 using System;
 using System.Collections.Generic;
+using System.Data;
 using System.Globalization;
+using System.Linq;
 using ClosedXML.Excel;
 
 namespace PSWriteOffice.Services.Excel;
@@ -87,4 +89,74 @@ public static partial class ExcelDocumentService
             yield return rowData;
         }
     }
+
+    private static IEnumerable<object> MapRowsToType(IEnumerable<IDictionary<string, object?>> rows, Type type)
+    {
+        var properties = type.GetProperties().Where(p => p.CanWrite).ToArray();
+        foreach (var row in rows)
+        {
+            var instance = Activator.CreateInstance(type);
+            if (instance == null)
+            {
+                continue;
+            }
+
+            foreach (var property in properties)
+            {
+                var matchingKey = row.Keys.FirstOrDefault(k => string.Equals(k, property.Name, StringComparison.OrdinalIgnoreCase));
+                if (matchingKey == null)
+                {
+                    continue;
+                }
+
+                var value = row[matchingKey];
+                if (value == null)
+                {
+                    property.SetValue(instance, null);
+                    continue;
+                }
+
+                try
+                {
+                    var targetType = Nullable.GetUnderlyingType(property.PropertyType) ?? property.PropertyType;
+                    var converted = Convert.ChangeType(value, targetType, CultureInfo.InvariantCulture);
+                    property.SetValue(instance, converted);
+                }
+                catch
+                {
+                    // ignore conversion failures
+                }
+            }
+
+            yield return instance;
+        }
+    }
+
+    private static DataTable BuildDataTable(IEnumerable<IDictionary<string, object?>> rows)
+    {
+        var table = new DataTable();
+        var columnsAdded = false;
+
+        foreach (var row in rows)
+        {
+            if (!columnsAdded)
+            {
+                foreach (var key in row.Keys)
+                {
+                    table.Columns.Add(key, typeof(object));
+                }
+
+                columnsAdded = true;
+            }
+
+            var dataRow = table.NewRow();
+            foreach (var key in row.Keys)
+            {
+                dataRow[key] = row[key] ?? DBNull.Value;
+            }
+            table.Rows.Add(dataRow);
+        }
+
+        return table;
+    }
 }

Sources/PSWriteOffice/Services/Excel/ExcelDocumentService.cs

@@ -1,5 +1,14 @@
+using System;
+using System.Collections.Generic;
+
 namespace PSWriteOffice.Services.Excel;
 
 public static partial class ExcelDocumentService
 {
+    public static object ConvertWorksheetData(IEnumerable<IDictionary<string, object?>> rows, Type? type, bool asDataTable)
+        => asDataTable
+            ? BuildDataTable(rows)
+            : type != null
+                ? MapRowsToType(rows, type)
+                : rows;
 }

Tests/ImportOfficeExcel.Tests.ps1

@@ -80,6 +80,43 @@ Describe 'Import-OfficeExcel cmdlet' {
         $rows[0].Column2 | Should -Be 30
     }
 
+    It 'imports data as specified type' {
+        class Person {
+            [string]$Name
+            [int]$Age
+        }
+
+        $path = Join-Path $TestDrive 'typed.xlsx'
+        New-Item -Path $path -ItemType File | Out-Null
+        $workbook = New-OfficeExcel
+        $sheet1 = New-OfficeExcelWorkSheet -Workbook $workbook -WorksheetName 'Data' -Option Replace
+        New-OfficeExcelValue -Worksheet $sheet1 -Row 1 -Column 1 -Value 'Name'
+        New-OfficeExcelValue -Worksheet $sheet1 -Row 1 -Column 2 -Value 'Age'
+        New-OfficeExcelValue -Worksheet $sheet1 -Row 2 -Column 1 -Value 'John'
+        New-OfficeExcelValue -Worksheet $sheet1 -Row 2 -Column 2 -Value 30
+        Save-OfficeExcel -Workbook $workbook -FilePath $path
+        $rows = Import-OfficeExcel -FilePath $path -Type ([Person])
+        $rows[0].GetType().FullName | Should -Be ([Person]).FullName
+        $rows[0].Name | Should -Be 'John'
+        $rows[0].Age | Should -Be 30
+    }
+
+    It 'imports data as DataTable' {
+        $path = Join-Path $TestDrive 'datatable.xlsx'
+        New-Item -Path $path -ItemType File | Out-Null
+        $workbook = New-OfficeExcel
+        $sheet1 = New-OfficeExcelWorkSheet -Workbook $workbook -WorksheetName 'Data' -Option Replace
+        New-OfficeExcelValue -Worksheet $sheet1 -Row 1 -Column 1 -Value 'Name'
+        New-OfficeExcelValue -Worksheet $sheet1 -Row 1 -Column 2 -Value 'Age'
+        New-OfficeExcelValue -Worksheet $sheet1 -Row 2 -Column 1 -Value 'Jane'
+        New-OfficeExcelValue -Worksheet $sheet1 -Row 2 -Column 2 -Value 31
+        Save-OfficeExcel -Workbook $workbook -FilePath $path
+        $table = Import-OfficeExcel -FilePath $path -AsDataTable
+        $table.GetType().FullName | Should -Be ([System.Data.DataTable]).FullName
+        $table.Rows.Count | Should -Be 1
+        $table.Rows[0].Name | Should -Be 'Jane'
+    }
+
     It 'throws for invalid path' {
         { Import-OfficeExcel -FilePath (Join-Path $TestDrive 'missing.xlsx') } | Should -Throw
     }