diff --git a/ICSharpCode.Decompiler/ICSharpCode.Decompiler.csproj b/ICSharpCode.Decompiler/ICSharpCode.Decompiler.csproj
index 387d453b5..dd2bd4a91 100644
--- a/ICSharpCode.Decompiler/ICSharpCode.Decompiler.csproj
+++ b/ICSharpCode.Decompiler/ICSharpCode.Decompiler.csproj
@@ -271,6 +271,8 @@
     <Compile Include="DotNetCore\DotNetCorePathFinder.cs" />
     <Compile Include="DotNetCore\DotNetCorePathFinderExtensions.cs" />
     <Compile Include="DotNetCore\UnresolvedAssemblyNameReference.cs" />
+    <Compile Include="IL\Instructions\StringToInt.cs" />
+    <Compile Include="IL\Instructions\UsingInstruction.cs" />
     <Compile Include="IL\Transforms\UsingTransform.cs" />
     <Compile Include="IL\ControlFlow\AsyncAwaitDecompiler.cs" />
     <Compile Include="IL\ControlFlow\ControlFlowGraph.cs" />
diff --git a/ICSharpCode.Decompiler/IL/Instructions.cs b/ICSharpCode.Decompiler/IL/Instructions.cs
index 015b312b7..c6f361279 100644
--- a/ICSharpCode.Decompiler/IL/Instructions.cs
+++ b/ICSharpCode.Decompiler/IL/Instructions.cs
@@ -158,6 +158,8 @@ namespace ICSharpCode.Decompiler.IL
 		/// <summary>Converts an array pointer (O) to a reference to the first element, or to a null reference if the array is null or empty.
 		/// Also used to convert a string to a reference to the first character.</summary>
 		ArrayToPointer,
+		/// <summary>Maps a string value to an integer. This is used in switch(string).</summary>
+		StringToInt,
 		/// <summary>Push a typed reference of type class onto the stack.</summary>
 		MakeRefAny,
 		/// <summary>Push the type token stored in a typed reference.</summary>
@@ -4021,6 +4023,87 @@ namespace ICSharpCode.Decompiler.IL
 	}
 }
 namespace ICSharpCode.Decompiler.IL
+{
+	/// <summary>Maps a string value to an integer. This is used in switch(string).</summary>
+	public sealed partial class StringToInt : ILInstruction
+	{
+		public static readonly SlotInfo ArgumentSlot = new SlotInfo("Argument", canInlineInto: true);
+		ILInstruction argument;
+		public ILInstruction Argument {
+			get { return this.argument; }
+			set {
+				ValidateChild(value);
+				SetChildInstruction(ref this.argument, value, 0);
+			}
+		}
+		protected sealed override int GetChildCount()
+		{
+			return 1;
+		}
+		protected sealed override ILInstruction GetChild(int index)
+		{
+			switch (index) {
+				case 0:
+					return this.argument;
+				default:
+					throw new IndexOutOfRangeException();
+			}
+		}
+		protected sealed override void SetChild(int index, ILInstruction value)
+		{
+			switch (index) {
+				case 0:
+					this.Argument = value;
+					break;
+				default:
+					throw new IndexOutOfRangeException();
+			}
+		}
+		protected sealed override SlotInfo GetChildSlot(int index)
+		{
+			switch (index) {
+				case 0:
+					return ArgumentSlot;
+				default:
+					throw new IndexOutOfRangeException();
+			}
+		}
+		public sealed override ILInstruction Clone()
+		{
+			var clone = (StringToInt)ShallowClone();
+			clone.Argument = this.argument.Clone();
+			return clone;
+		}
+		public override StackType ResultType { get { return StackType.I4; } }
+		protected override InstructionFlags ComputeFlags()
+		{
+			return argument.Flags;
+		}
+		public override InstructionFlags DirectFlags {
+			get {
+				return InstructionFlags.None;
+			}
+		}
+		public override void AcceptVisitor(ILVisitor visitor)
+		{
+			visitor.VisitStringToInt(this);
+		}
+		public override T AcceptVisitor<T>(ILVisitor<T> visitor)
+		{
+			return visitor.VisitStringToInt(this);
+		}
+		public override T AcceptVisitor<C, T>(ILVisitor<C, T> visitor, C context)
+		{
+			return visitor.VisitStringToInt(this, context);
+		}
+		protected internal override bool PerformMatch(ILInstruction other, ref Patterns.Match match)
+		{
+			var o = other as StringToInt;
+			return o != null && this.argument.PerformMatch(o.argument, ref match);
+		}
+	}
+}
+namespace ICSharpCode.Decompiler.IL
 {
 	/// <summary>Push a typed reference of type class onto the stack.</summary>
 	public sealed partial class MakeRefAny : UnaryInstruction
@@ -4633,6 +4716,10 @@ namespace ICSharpCode.Decompiler.IL
 		{
 			Default(inst);
 		}
+		protected internal virtual void VisitStringToInt(StringToInt inst)
+		{
+			Default(inst);
+		}
 		protected internal virtual void VisitMakeRefAny(MakeRefAny inst)
 		{
 			Default(inst);
@@ -4919,6 +5006,10 @@ namespace ICSharpCode.Decompiler.IL
 		{
 			return Default(inst);
 		}
+		protected internal virtual T VisitStringToInt(StringToInt inst)
+		{
+			return Default(inst);
+		}
 		protected internal virtual T VisitMakeRefAny(MakeRefAny inst)
 		{
 			return Default(inst);
@@ -5205,6 +5296,10 @@ namespace ICSharpCode.Decompiler.IL
 		{
 			return Default(inst, context);
 		}
+		protected internal virtual T VisitStringToInt(StringToInt inst, C context)
+		{
+			return Default(inst, context);
+		}
 		protected internal virtual T VisitMakeRefAny(MakeRefAny inst, C context)
 		{
 			return Default(inst, context);
@@ -5294,6 +5389,7 @@ namespace ICSharpCode.Decompiler.IL
 			"ldlen",
 			"ldelema",
 			"array.to.pointer",
+			"string.to.int",
 			"mkrefany",
 			"refanytype",
 			"refanyval",
diff --git a/ICSharpCode.Decompiler/IL/Instructions.tt b/ICSharpCode.Decompiler/IL/Instructions.tt
index 2b28a9efe..f25e3fa0d 100644
--- a/ICSharpCode.Decompiler/IL/Instructions.tt
+++ b/ICSharpCode.Decompiler/IL/Instructions.tt
@@ -220,6 +220,8 @@
 		new OpCode("array.to.pointer", "Converts an array pointer (O) to a reference to the first element, or to a null reference if the array is null or empty." + Environment.NewLine
 			+ "Also used to convert a string to a reference to the first character.",
 			CustomArguments("array"), ResultType("Ref")),
+		new OpCode("string.to.int", "Maps a string value to an integer. This is used in switch(string).",
+			CustomArguments("argument"), CustomConstructor, CustomWriteTo, ResultType("I4")),
 
 		new OpCode("mkrefany", "Push a typed reference of type class onto the stack.",
 			CustomClassName("MakeRefAny"), Unary, HasTypeOperand, ResultType("O")),
diff --git a/ICSharpCode.Decompiler/IL/Instructions/LockInstruction.cs b/ICSharpCode.Decompiler/IL/Instructions/LockInstruction.cs
index f0c1b1ebc..36cd8380e 100644
--- a/ICSharpCode.Decompiler/IL/Instructions/LockInstruction.cs
+++ b/ICSharpCode.Decompiler/IL/Instructions/LockInstruction.cs
@@ -38,36 +38,4 @@ namespace ICSharpCode.Decompiler.IL
 			output.Write("}");
 		}
 	}
-
-	/// <summary>
-	/// IL using instruction.
-	/// Equivalent to:
-	/// <code>
-	/// stloc v(resourceExpression)
-	/// try {
-	///    body
-	/// } finally {
-	///    v?.Dispose();
-	/// }
-	/// </code>
-	/// </summary>
-	/// <remarks>
-	/// The value of v is undefined after the end of the body block.
-	/// </remarks>
-	partial class UsingInstruction
-	{
-		public override void WriteTo(ITextOutput output, ILAstWritingOptions options)
-		{
-			output.Write("using (");
-			Variable.WriteTo(output);
-			output.Write(" = ");
-			ResourceExpression.WriteTo(output, options);
-			output.WriteLine(") {");
-			output.Indent();
-			Body.WriteTo(output, options);
-			output.Unindent();
-			output.WriteLine();
-			output.Write("}");
-		}
-	}
 }
diff --git a/ICSharpCode.Decompiler/IL/Instructions/StringToInt.cs b/ICSharpCode.Decompiler/IL/Instructions/StringToInt.cs
new file mode 100644
index 000000000..f804a3928
--- /dev/null
+++ b/ICSharpCode.Decompiler/IL/Instructions/StringToInt.cs
@@ -0,0 +1,45 @@
+// Copyright (c) 2017 Siegfried Pammer
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of this
+// software and associated documentation files (the "Software"), to deal in the Software
+// without restriction, including without limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
+// to whom the Software is furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all copies or
+// substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
+// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+
+namespace ICSharpCode.Decompiler.IL
+{
+	partial class StringToInt
+	{
+		public string[] Map { get; }
+
+		public StringToInt(ILInstruction argument, string[] map)
+			: base(OpCode.StringToInt)
+		{
+			this.Argument = argument;
+			this.Map = map;
+		}
+
+		public override void WriteTo(ITextOutput output, ILAstWritingOptions options)
+		{
+			output.Write("string.to.int (");
+			Argument.WriteTo(output, options);
+			output.Write(", { ");
+			for (int i = 0; i < Map.Length; i++) {
+				if (i > 0) output.Write(", ");
+				output.Write($"[{i}] = \"{Map[i]}\"");
+			}
+			output.Write(" })");
+		}
+	}
+}
diff --git a/ICSharpCode.Decompiler/IL/Instructions/UsingInstruction.cs b/ICSharpCode.Decompiler/IL/Instructions/UsingInstruction.cs
new file mode 100644
index 000000000..795be5914
--- /dev/null
+++ b/ICSharpCode.Decompiler/IL/Instructions/UsingInstruction.cs
@@ -0,0 +1,53 @@
+// Copyright (c) 2017 Siegfried Pammer
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of this
+// software and associated documentation files (the "Software"), to deal in the Software
+// without restriction, including without limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
+// to whom the Software is furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all copies or
+// substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
+// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+
+namespace ICSharpCode.Decompiler.IL
+{
+	/// <summary>
+	/// IL using instruction.
+	/// Equivalent to:
+	/// <code>
+	/// stloc v(resourceExpression)
+	/// try {
+	///    body
+	/// } finally {
+	///    v?.Dispose();
+	/// }
+	/// </code>
+	/// </summary>
+	/// <remarks>
+	/// The value of v is undefined after the end of the body block.
+	/// </remarks>
+	partial class UsingInstruction
+	{
+		public override void WriteTo(ITextOutput output, ILAstWritingOptions options)
+		{
+			output.Write("using (");
+			Variable.WriteTo(output);
+			output.Write(" = ");
+			ResourceExpression.WriteTo(output, options);
+			output.WriteLine(") {");
+			output.Indent();
+			Body.WriteTo(output, options);
+			output.Unindent();
+			output.WriteLine();
+			output.Write("}");
+		}
+	}
+}