Add option to IgnoreHeaderUnderscores

src/CsvHelper.Tests/CsvReaderTests.cs

@@ -700,6 +700,23 @@ public void SpacesInHeaderTest()
 			Assert.AreEqual( "one", data[0].StringColumn );
 		}
 
+		[TestMethod]
+		public void UnderscoresInHeaderTest()
+		{
+			var queue = new Queue<string[]>();
+			queue.Enqueue(new[] { "_Int_Column_", "_String_Column_" });
+			queue.Enqueue(new[] { "1", "one" });
+			queue.Enqueue(null);
+			var parserMock = new ParserMock(queue);
+			var reader = new CsvReader(parserMock);
+			reader.Configuration.IgnoreHeaderUnderscores = true;
+			var data = reader.GetRecords<TestDefaultValues>().ToList();
+			Assert.IsNotNull(data);
+			Assert.AreEqual(1, data.Count);
+			Assert.AreEqual(1, data[0].IntColumn);
+			Assert.AreEqual("one", data[0].StringColumn);
+		}
+
 		[TestMethod]
 		public void BooleanTypeConverterTest()
 		{

src/CsvHelper/Configuration/CsvConfiguration.cs

@@ -121,6 +121,13 @@ public virtual bool IsHeaderCaseSensitive
 		/// </summary>
 		public virtual bool IgnoreHeaderWhiteSpace { get; set; }
 
+		/// <summary>
+		/// Gets or sets a value indicating whether matcher header
+		/// column names will ignore underscores. True to ignore
+		/// underscores, otherwise false. Default is false.
+		/// </summary>
+		public virtual bool IgnoreHeaderUnderscores { get; set; }
+
 		/// <summary>
 		/// Gets or sets a value indicating whether references
 		/// should be ignored when auto mapping. True to ignore

src/CsvHelper/CsvReader.cs

@@ -1177,6 +1177,12 @@ protected virtual int GetFieldIndex( string[] names, int index = 0, bool isTryGe
 			foreach( var pair in namedIndexes )
 			{
 				var namedIndex = pair.Key;
+
+				if ( configuration.IgnoreHeaderUnderscores )
+				{
+					namedIndex = namedIndex.Replace( "_", string.Empty );
+				}
+
 				if( configuration.IgnoreHeaderWhiteSpace )
 				{
 					namedIndex = Regex.Replace( namedIndex, "\\s", string.Empty );