DI Refactoring

1 files changed, 17 insertions, 7 deletions

diff --git a/RhSolutions.ExcelExtensions/Columns.cs b/RhSolutions.ExcelExtensions/Columns.cs
index 1fbc0ef..014b755 100644
--- a/RhSolutions.ExcelExtensions/Columns.cs
+++ b/RhSolutions.ExcelExtensions/Columns.cs
@@ -4,35 +4,45 @@ namespace RhSolutions.ExcelExtensions;
 
 public class Columns : IEnumerable<Column>
 {
-    public Range Range { get; }
     public Table ParentTable { get; }
     public int Length
     {
-        get => Range.Columns.Count;
+        get => _range.Columns.Count;
     }
+    private Column[] _columns;
+    private Range _range;
 
-    public Columns(Range range, Table parentTable)
+    public Columns(Table parentTable)
     {
-        Range = range;
         ParentTable = parentTable;
+        _range = parentTable.Range;
+        _columns = new Column[Length];
     }
 
     public Column this[int index]
     {
         get
         {
-            if (index < 0 || index + 1 > Range.Columns.Count)
+            if (index < 0 || index >= Length)
             {
                 throw new IndexOutOfRangeException();
             }
 
-            return new Column(Range.Columns[index + 1], ParentTable);
+            if (_columns[index] == null)
+            {
+                _columns[index] = new Column(_range.Columns[index + 1], ParentTable);
+                return _columns[index];
+            }
+            else
+            {
+                return _columns[index];
+            }
         }
     }
 
     public IEnumerator<Column> GetEnumerator()
     {
-        return new ColumnsEnumerator(Range, ParentTable);
+        return new ColumnsEnumerator(this);
     }
 
     IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();