From ba1b807dcd9bdf26fa92fd5af6f5ae579488cec4 Mon Sep 17 00:00:00 2001
From: Manny Lertpatthanakul <jml@alum.wpi.edu>
Date: Sat, 14 Jul 2018 09:32:40 -0400
Subject: [PATCH] Add ability to specify the equality comparer used for
 matching column names.  Useful for allowing for case-insensitive comparisons

---
 LINQtoCSV/CsvFileDescription.cs                 |   8 +++++++-
 LINQtoCSV/FieldMapper.cs                        |   4 +++-
 TestConsoleApplication/ProductData.cs           |   2 +-
 TestConsoleApplication/Program.cs               |   3 ++-
 .../TestFiles/output_anon.csv                   |   6 +++---
 .../TestFiles/output_names_nl.csv               | Bin 882 -> 882 bytes
 .../TestFiles/output_newdata_names_nl.csv       | Bin 652 -> 652 bytes
 7 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/LINQtoCSV/CsvFileDescription.cs b/LINQtoCSV/CsvFileDescription.cs
index b983ca8..f018586 100644
--- a/LINQtoCSV/CsvFileDescription.cs
+++ b/LINQtoCSV/CsvFileDescription.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Globalization;
 using System.Text;
 
@@ -90,7 +91,12 @@ public int MaximumNbrExceptions
         public bool UseFieldIndexForReadingData { get; set; }
         public bool UseOutputFormatForParsingCsvValue { get; set; }
         public bool IgnoreTrailingSeparatorChar { get; set; }
-        
+
+        /// <summary>
+        /// Allows for override of the string comparison strategy
+        /// </summary>
+        public IEqualityComparer<string> ColumnEqualityComparer { get; set; }
+
         /// <summary>
         /// If set to true, wil read only the fields specified as attributes, and will discard other fields in the CSV file
         /// </summary>
diff --git a/LINQtoCSV/FieldMapper.cs b/LINQtoCSV/FieldMapper.cs
index 9ef9dfc..853fa4e 100644
--- a/LINQtoCSV/FieldMapper.cs
+++ b/LINQtoCSV/FieldMapper.cs
@@ -267,7 +267,9 @@ public FieldMapper(CsvFileDescription fileDescription, string fileName, bool wri
             m_fileDescription = fileDescription;
             m_fileName = fileName;
 
-            m_NameToInfo = new Dictionary<string, TypeFieldInfo>();
+            m_NameToInfo = fileDescription.ColumnEqualityComparer != null ?
+                new Dictionary<string, TypeFieldInfo>(fileDescription.ColumnEqualityComparer) :
+                new Dictionary<string, TypeFieldInfo>();
 
             AnalyzeType(
                 typeof(T), 
diff --git a/TestConsoleApplication/ProductData.cs b/TestConsoleApplication/ProductData.cs
index 847c9f2..bbe0f1e 100644
--- a/TestConsoleApplication/ProductData.cs
+++ b/TestConsoleApplication/ProductData.cs
@@ -25,7 +25,7 @@ class ProductData
         public DateTime launchTime;
 
         // Can use both fields and properties
-        [CsvColumn(FieldIndex = 4, CanBeNull = false, OutputFormat = "#,000.000")]
+        [CsvColumn(FieldIndex = 4, CanBeNull = false, OutputFormat = "#,000.000", Name = "Weight")]
         public double weight { get; set; }
 
         // Following field has no CsvColumn attribute.
diff --git a/TestConsoleApplication/Program.cs b/TestConsoleApplication/Program.cs
index e82ff17..60fdaf9 100644
--- a/TestConsoleApplication/Program.cs
+++ b/TestConsoleApplication/Program.cs
@@ -29,7 +29,8 @@ static void Main(string[] args)
                 SeparatorChar = ',', // default is ','
                 FirstLineHasColumnNames = true,
                 EnforceCsvColumnAttribute = false, // default is false
-                FileCultureName = "en-US" // default is the current culture
+                FileCultureName = "en-US", // default is the current culture
+                ColumnEqualityComparer = StringComparer.CurrentCultureIgnoreCase
             };
 
             try
diff --git a/TestConsoleApplication/TestFiles/output_anon.csv b/TestConsoleApplication/TestFiles/output_anon.csv
index f22ff9c..4f91285 100644
--- a/TestConsoleApplication/TestFiles/output_anon.csv
+++ b/TestConsoleApplication/TestFiles/output_anon.csv
@@ -1,4 +1,4 @@
 Markup,InShops,ProductName
-39150.0,2/01/1985 12:00:00 AM,mouse trap
-270.060,23/05/2008 12:00:00 AM,moonbuggy
-6004.0,29/02/2004 12:00:00 AM,dog house
+39150.0,1/2/1985 12:00:00 AM,mouse trap
+270.060,5/23/2008 12:00:00 AM,moonbuggy
+6004.0,2/29/2004 12:00:00 AM,dog house
diff --git a/TestConsoleApplication/TestFiles/output_names_nl.csv b/TestConsoleApplication/TestFiles/output_names_nl.csv
index f7ec0a3f0f5ca6e050bffdf9eab2e6d3eafab2fd..4a701a7f10132e0e987187c2467e3451df96958e 100644
GIT binary patch
delta 12
Tcmeyw_K9tR8DscHb8BV*Ams!#

delta 12
Tcmeyw_K9tR8DsfIb8BV*A%z50

diff --git a/TestConsoleApplication/TestFiles/output_newdata_names_nl.csv b/TestConsoleApplication/TestFiles/output_newdata_names_nl.csv
index 35c7ee071d269c242e2f3f49cfcaf62619a0e2fd..d8ba3adda4b62a996db0fc375a9701bea35b867f 100644
GIT binary patch
delta 37
scmeBS?O~l@#uz@)d?Tw7gD!*N#<%i}+=dK>3<?an45<v6lf{`z0k_!*_5c6?

delta 37
scmeBS?O~l@##lbld?TwNgD!*7#<%i}+y)G$3<?Z+4EYRYlf{`z0lZ2HF#rGn