Fix problem with DynamicParameters.Get<T> being called before the parameters have been added

Dapper NET40/SqlMapper.cs

@@ -4851,7 +4851,9 @@ public IEnumerable<string> ParameterNames
         /// <returns>The value, note DBNull.Value is not returned, instead the value is returned as null</returns>
         public T Get<T>(string name)
         {
-            var val = parameters[Clean(name)].AttachedParam.Value;
+            var paramInfo = parameters[Clean(name)];
+            var attachedParam = paramInfo.AttachedParam;
+            object val = attachedParam == null ? paramInfo.Value : attachedParam.Value;
             if (val == DBNull.Value)
             {
                 if (default(T) != null)

Tests/Tests.cs

@@ -4565,5 +4565,13 @@ public void TestPostresqlArrayParameters()
             }
         }
 #endif
+
+        public void SO30156367_DynamicParamsWithoutExec()
+        {
+            var dbParams = new DynamicParameters();
+            dbParams.Add("Field1", 1);
+            var value = dbParams.Get<int>("Field1");
+            value.IsEqualTo(1);
+        }
     }
 }

dapper.nuspec

@@ -2,7 +2,7 @@
 <package xmlns="http://schemas.microsoft.com/packaging/2010/07/nuspec.xsd">
   <metadata schemaVersion="2">
     <id>Dapper</id>
-    <version>1.40</version>
+    <version>1.42</version>
     <title>Dapper dot net</title>
     <authors>Sam Saffron,Marc Gravell</authors>
     <owners>Sam Saffron,Marc Gravell</owners>