Fix for C# paramArray and refactor on arguments mismatch

Author: ChrisBardsley

CefSharp.Example/Resources/Home.html

@@ -351,6 +351,14 @@ <h3 id="features-javascript-integration">JavaScript integration</h3>
                         objects.
                     </p>
                     <h3>Hooks by which you can modify and/or override certain features of the web browsing</h3>
+                    <p>
+                        A fix to allow params to be used by the .NET methods called by the javascript<br />
+                        <button onclick="boundEvent.methodWithParams('test', 'hello-world')">With 1 Params</button>
+                        <button onclick="boundEvent.methodWithParams('test', 'hello-world', 'chris was here')">With 2 Params</button>
+                        <button onclick="boundEvent.methodWithParams('test')">With no Params</button>
+                        <button onclick="boundEvent.methodWithoutParams('test', 'hello')">Normal Method</button>
+                        <button onclick="boundEvent.methodWithoutAnything()">Normal Method No Params</button>
+                    </p>
                 </div>
                 <div class="bs-docs-section">
                     <div class="page-header">

CefSharp.Example/ScriptedMethodsBoundObject.cs

@@ -2,6 +2,7 @@
 //
 // Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
 using System;
+using System.Linq;
 
 namespace CefSharp.Example
 {
@@ -35,5 +36,26 @@ public void RaiseEvent(string eventName, object eventData = null)
                 EventArrived(eventName, eventData);
             }
         }
+
+        /// <summary>
+        /// Demonstrates the use of params as an argument in a bound object
+        /// </summary>
+        /// <param name="name">Dummy Argument</param>
+        /// <param name="args">Params Argument</param>
+        public void MethodWithParams(string name, params object[] args)
+        {
+            var test = args.ElementAtOrDefault(0);
+            var test2 = args.ElementAtOrDefault(1);
+        }
+
+        public void MethodWithoutParams(string name, string arg2)
+        {
+            var test = arg2;
+        }
+
+        public void methodWithoutAnything()
+        {
+            var test = "";
+        }
     }
 }

CefSharp/CefSharp.csproj

@@ -89,6 +89,7 @@
     <Compile Include="IDomNode.cs" />
     <Compile Include="IFindHandler.cs" />
     <Compile Include="Internals\CommandLineArgsParser.cs" />
+    <Compile Include="Internals\MethodParameter.cs" />
     <Compile Include="IPluginHandler.cs" />
     <Compile Include="IPopupFeatures.cs" />
     <Compile Include="IRenderProcessMessageHandler.cs" />

CefSharp/Internals/JavascriptMethod.cs

@@ -3,6 +3,7 @@
 // Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
 
 using System;
+using System.Collections.Generic;
 using System.Runtime.Serialization;
 
 namespace CefSharp.Internals
@@ -33,6 +34,9 @@ public class JavascriptMethod
         [DataMember]
         public string JavascriptName { get; set; }
 
+        [DataMember]
+        public List<MethodParameter> MethodParameters { get; set; }
+
         /// <summary>
         /// Number of Params this function exepects
         /// </summary>

CefSharp/Internals/JavascriptObjectRepository.cs

@@ -104,15 +104,33 @@ public bool TryCallMethod(long objectId, string name, object[] parameters, out o
 
             try
             {
-                // Do we have enough arguments? Add Type.Missing for any that we don't have incase of optional params
+                //Fix for C# paramArray and refactor on arguments mismatch 03/22/2016
                 var missingParams = method.ParameterCount - parameters.Length;
-                if (missingParams > 0)
+                if (missingParams > 0 || method.MethodParameters.Any(t => t.IsParamArray))
                 {
-                    var paramList = new List<object>(parameters);
+                    var paramList = new List<object>();
 
-                    for (var i = 0; i < missingParams; i++)
+                    for (int i = 0; i < method.MethodParameters.Count; i++)
                     {
-                        paramList.Add(Type.Missing);
+                        object jsParam = parameters.ElementAtOrDefault(i);
+                        if (jsParam == null && !method.MethodParameters[i].IsParamArray)
+                        {
+                            paramList.Add(Type.Missing);
+                        }
+                        else if (method.MethodParameters[i].IsParamArray)
+                        {
+                            List<object> convertedParams = new List<object>();
+                            for (int s = i; s < parameters.Count(); s++)
+                            {
+                                convertedParams.Add(parameters[s]);
+                            }
+                            paramList.Add(convertedParams.ToArray());
+                            break;
+                        }
+                        else
+                        {
+                            paramList.Add(jsParam);
+                        }
                     }
 
                     parameters = paramList.ToArray();
@@ -287,6 +305,14 @@ private static JavascriptMethod CreateJavaScriptMethod(MethodInfo methodInfo, bo
             jsMethod.JavascriptName = GetJavascriptName(methodInfo.Name, camelCaseJavascriptNames);
             jsMethod.Function = methodInfo.Invoke;
             jsMethod.ParameterCount = methodInfo.GetParameters().Length;
+            jsMethod.MethodParameters = methodInfo.GetParameters()
+                .Select(t => new MethodParameter()
+                { Name = t.Name,
+                    ParameterType = t.ParameterType,
+                    Position = t.Position,
+                    IsParamArray = t.GetCustomAttributes(typeof(ParamArrayAttribute), false).Length > 0
+                }).ToList();
+            
 
             return jsMethod;
         }

CefSharp/Internals/MethodParameter.cs

@@ -0,0 +1,20 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.Serialization;
+using System.Text;
+
+namespace CefSharp.Internals
+{
+    [DataContract]
+    public class MethodParameter
+    {
+        public String Name { get; set; }
+
+        public Type ParameterType { get; set; }
+
+        public Boolean IsParamArray { get; set; }
+
+        public Int32 Position { get; set; }
+    }
+}

NuGet.config

@@ -5,5 +5,6 @@
     </activePackageSource>
   <packageSources>
     <add key="cefsharp-myget" value="https://www.myget.org/F/cefsharp/" />
+    <add key="nuget.org" value="https://api.nuget.org/v3/index.json" protocolVersion="3" />
   </packageSources>
 </configuration>