Added Clean Content Function (discord-net#174)

* Added Clean Content Function

* Fixed Spelling problems and bad var handling

* Add StripMarkDown Method

src/Discord.Net.Core/Discord.Net.Core.xml

@@ -11423,6 +11423,13 @@
             <param name="text">The text to format.</param>
             <returns>Gets the formatted block quote text.</returns>
         </member>
+        <member name="M:Discord.Format.StripMarkDown(System.String)">
+            <summary>
+            Remove discord supported markdown from text.
+            </summary>
+            <param name="text">The to remove markdown from.</param>
+            <returns>Gets the unformatted text.</returns>
+        </member>
         <member name="F:Discord.GatewayIntents.None">
             <summary> This intent includes no events </summary>
         </member>

src/Discord.Net.Core/Format.cs

@@ -1,4 +1,5 @@
 using System.Text;
+using System.Text.RegularExpressions;
 
 namespace Discord
 {
@@ -91,5 +92,17 @@ public static string BlockQuote(string text)
 
             return $">>> {text}";
         }
+
+        /// <summary>
+        /// Remove discord supported markdown from text.
+        /// </summary>
+        /// <param name="text">The to remove markdown from.</param>
+        /// <returns>Gets the unformatted text.</returns>
+        public static string StripMarkDown(string text)
+        {
+            //Remove discord supported markdown
+            var newText = Regex.Replace(text, @"(\*|_|`|~|>|\\)", "");
+            return newText;
+        }
     }
 }

src/Discord.Net.WebSocket/Entities/Messages/SocketMessage.cs

@@ -38,6 +38,9 @@ public abstract class SocketMessage : SocketEntity<ulong>, IMessage
         /// <inheritdoc />
         public string Content { get; private set; }
 
+        /// <inheritdoc />
+        public string CleanContent => SanitizeMessage();
+
         /// <inheritdoc />
         public DateTimeOffset CreatedAt => SnowflakeUtils.FromSnowflake(Id);
         /// <inheritdoc />
@@ -139,7 +142,11 @@ internal virtual void Update(ClientState state, Model model)
                 _timestampTicks = model.Timestamp.Value.UtcTicks;
 
             if (model.Content.IsSpecified)
+            {
                 Content = model.Content.Value;
+                //Update CleanContent Property
+                SanitizeMessage();
+            }
 
             if (model.Application.IsSpecified)
             {
@@ -265,6 +272,13 @@ public Task DeleteAsync(RequestOptions options = null)
         /// <inheritdoc />
         IReadOnlyCollection<IStickerItem> IMessage.Stickers => Stickers;
 
+        internal string  SanitizeMessage()
+        {
+            var newContent = MentionUtils.Resolve(this, 0, TagHandling.Sanitize, TagHandling.Sanitize, TagHandling.Sanitize, TagHandling.Sanitize, TagHandling.Sanitize);
+            newContent = Format.StripMarkDown(newContent);
+            return newContent;
+        }
+
         internal void AddReaction(SocketReaction reaction)
         {
             _reactions.Add(reaction);

test/Discord.Net.Tests.Unit/FormatTests.cs

@@ -59,5 +59,20 @@ public void BlockQuote(string input, string expected)
         {
             Assert.Equal(expected, Format.BlockQuote(input));
         }
+
+        [Theory]
+        [InlineData("", "")]
+        [InlineData("\n", "\n")]
+        [InlineData("**hi**", "hi")]
+        [InlineData("__uwu__", "uwu")]
+        [InlineData(">>__uwu__", "uwu")]
+        [InlineData("```uwu```", "uwu")]
+        [InlineData("~uwu~", "uwu")]
+        [InlineData("berries __and__ *Cream**, i'm a little lad who loves berries and cream", "berries and Cream, i'm a little lad who loves berries and cream")]
+        public void StripMarkdown(string input, string expected)
+        {
+            var test = Format.StripMarkDown(input);
+            Assert.Equal(expected, test);
+        }
     }
 }