From 8b8ff190d98d20126d515b821645d957d1335ca6 Mon Sep 17 00:00:00 2001
From: Mark Heath <mark.heath@gmail.com>
Date: Sat, 22 Jul 2017 11:51:40 +0100
Subject: [PATCH] improved error message for channel index out of range #208

---
 NAudio/CoreAudioApi/AudioMeterInformationChannels.cs | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/NAudio/CoreAudioApi/AudioMeterInformationChannels.cs b/NAudio/CoreAudioApi/AudioMeterInformationChannels.cs
index 9dba54f2..668927c4 100644
--- a/NAudio/CoreAudioApi/AudioMeterInformationChannels.cs
+++ b/NAudio/CoreAudioApi/AudioMeterInformationChannels.cs
@@ -30,7 +30,7 @@ namespace NAudio.CoreAudioApi
     /// </summary>
     public class AudioMeterInformationChannels
     {
-        readonly IAudioMeterInformation audioMeterInformation;
+        private readonly IAudioMeterInformation audioMeterInformation;
 
         /// <summary>
         /// Metering Channel Count
@@ -54,8 +54,14 @@ public float this[int index]
         {
             get
             {
+                var channels = Count;
+                if (index >= channels)
+                {
+                    throw new ArgumentOutOfRangeException(nameof(index),
+                        $"Peak index cannot be greater than number of channels ({channels})");
+                }
                 var peakValues = new float[Count];
-                GCHandle Params = GCHandle.Alloc(peakValues, GCHandleType.Pinned);
+                var Params = GCHandle.Alloc(peakValues, GCHandleType.Pinned);
                 Marshal.ThrowExceptionForHR(audioMeterInformation.GetChannelsPeakValues(peakValues.Length, Params.AddrOfPinnedObject()));
                 Params.Free();
                 return peakValues[index];