Use loop variable instead of 0 (#1334)

* Use loop variable instead of 0

* Changed unit test, added additional nesting level

Dapper.Tests/AsyncTests.cs

@@ -476,7 +476,7 @@ public async Task Issue346_QueryAsyncConvert()
         public async Task TestSupportForDynamicParametersOutputExpressionsAsync()
         {
             {
-                var bob = new Person { Name = "bob", PersonId = 1, Address = new Address { PersonId = 2 } };
+                var bob = new Person { Name = "bob", PersonId = 1, Address = new Address { PersonId = 2, Index = new Index() } };
 
                 var p = new DynamicParameters(bob);
                 p.Output(bob, b => b.PersonId);
@@ -484,19 +484,22 @@ public async Task TestSupportForDynamicParametersOutputExpressionsAsync()
                 p.Output(bob, b => b.NumberOfLegs);
                 p.Output(bob, b => b.Address.Name);
                 p.Output(bob, b => b.Address.PersonId);
+                p.Output(bob, b => b.Address.Index.Id);
 
                 await connection.ExecuteAsync(@"
 SET @Occupation = 'grillmaster' 
 SET @PersonId = @PersonId + 1 
 SET @NumberOfLegs = @NumberOfLegs - 1
 SET @AddressName = 'bobs burgers'
-SET @AddressPersonId = @PersonId", p).ConfigureAwait(false);
+SET @AddressPersonId = @PersonId
+SET @AddressIndexId = '01088'", p).ConfigureAwait(false);
 
                 Assert.Equal("grillmaster", bob.Occupation);
                 Assert.Equal(2, bob.PersonId);
                 Assert.Equal(1, bob.NumberOfLegs);
                 Assert.Equal("bobs burgers", bob.Address.Name);
                 Assert.Equal(2, bob.Address.PersonId);
+                Assert.Equal("01088", bob.Address.Index.Id);
             }
         }
 

Dapper.Tests/SharedTypes/Address.cs

-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-
-namespace Dapper.Tests
+namespace Dapper.Tests
 {
     public class Address
     {
         public int AddressId { get; set; }
         public string Name { get; set; }
         public int PersonId { get; set; }
+        public Index Index { get; set; }
     }
 }

Dapper.Tests/SharedTypes/Index.cs

+namespace Dapper.Tests
+{
+    public class Index
+    {
+        public string Id { get; set; }
+    }
+}

Dapper/DynamicParameters.cs

@@ -407,10 +407,9 @@ public DynamicParameters Output<T>(T target, Expression<Func<T, object>> express
             il.Emit(OpCodes.Castclass, typeof(T));    // [T]
 
             // Count - 1 to skip the last member access
-            var i = 0;
-            for (; i < (chain.Count - 1); i++)
+            for (var i = 0; i < chain.Count - 1; i++)
             {
-                var member = chain[0].Member;
+                var member = chain[i].Member;
 
                 if (member is PropertyInfo)
                 {