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AspClassic.VBScript/Binders/VBScriptGetIndexBinder.cs

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+using System;
+using System.Collections.Generic;
+//using System.Text;
+using System.Reflection;
+using System.Dynamic;
+#if USE35
+using AspClassic.Scripting.Ast;
+using AspClassic.Scripting.ComInterop;
+#else
+using System.Linq;
+using System.Linq.Expressions;
+using AspClassic.Scripting.ComInterop;
+#endif
+using Dlrsoft.VBScript.Runtime;
+
+namespace Dlrsoft.VBScript.Binders
+{
+    public class VBScriptGetIndexBinder : GetIndexBinder
+    {
+        public VBScriptGetIndexBinder(CallInfo callinfo)
+            : base(callinfo)
+        {
+        }
+
+        public override DynamicMetaObject FallbackGetIndex(
+                     DynamicMetaObject target, DynamicMetaObject[] indexes,
+                     DynamicMetaObject errorSuggestion)
+        {
+#if !SILVERLIGHT
+            // First try COM binding.
+            DynamicMetaObject result;
+            if (ComBinder.TryBindGetIndex(this, target, indexes, out result))
+            {
+                return result;
+            }
+#endif
+            // Defer if any object has no value so that we evaulate their
+            // Expressions and nest a CallSite for the InvokeMember.
+            if (!target.HasValue || indexes.Any((a) => !a.HasValue))
+            {
+                var deferArgs = new DynamicMetaObject[indexes.Length + 1];
+                for (int i = 0; i < indexes.Length; i++)
+                {
+                    deferArgs[i + 1] = indexes[i];
+                }
+                deferArgs[0] = target;
+                return Defer(deferArgs);
+            }
+
+            var restrictions = RuntimeHelpers.GetTargetArgsRestrictions(
+                                                  target, indexes, false);
+
+            if (target.HasValue && target.Value == null)
+            {
+                return errorSuggestion?? RuntimeHelpers.CreateThrow(target,
+                    indexes,
+                    restrictions,
+                    typeof(NullReferenceException),
+                    "Object reference not set to an instance of an object.");
+            }
+            var indexingExpr = RuntimeHelpers.EnsureObjectResult(
+                                  RuntimeHelpers.GetIndexingExpression(target,
+                                                                       indexes));
+            return new DynamicMetaObject(indexingExpr, restrictions);
+        }
+    }
+}