From cbc8695ae0c8c2c2d1ac1fc4546d81e0967ef716 Mon Sep 17 00:00:00 2001
From: Stephen Toub <stoub@microsoft.com>
Date: Tue, 14 Feb 2023 16:29:25 -0500
Subject: [PATCH] Use string interpolation in a few more places (#82096)

Places where we'd otherwise be allocating for at least one of the subcomponents.
---
 .../System.Formats.Asn1/src/System/Formats/Asn1/Asn1Tag.cs    | 2 +-
 .../System.Net.Mail/src/System/Net/Mail/SmtpClient.cs         | 2 +-
 .../System.Net.Requests/src/System/Net/HttpWebRequest.cs      | 2 +-
 .../src/System/Net/ServicePointManager.cs                     | 4 ++--
 .../src/System/Diagnostics/Tracing/ActivityTracker.cs         | 2 +-
 .../src/System/Reflection/DispatchProxyGenerator.cs           | 2 +-
 6 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/Asn1Tag.cs b/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/Asn1Tag.cs
index 691750765e31..01a6ae342525 100644
--- a/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/Asn1Tag.cs
+++ b/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/Asn1Tag.cs
@@ -472,7 +472,7 @@ public override string ToString()
             }
             else
             {
-                classAndValue = TagClass + "-" + TagValue;
+                classAndValue = $"{TagClass}-{TagValue}";
             }
 
             if (IsConstructed)
diff --git a/src/libraries/System.Net.Mail/src/System/Net/Mail/SmtpClient.cs b/src/libraries/System.Net.Mail/src/System/Net/Mail/SmtpClient.cs
index 591b0dab8bdf..eb97f48260cf 100644
--- a/src/libraries/System.Net.Mail/src/System/Net/Mail/SmtpClient.cs
+++ b/src/libraries/System.Net.Mail/src/System/Net/Mail/SmtpClient.cs
@@ -272,7 +272,7 @@ public ServicePoint ServicePoint
                 // be usable, whereas in .NET Framework it throws an exception that "This property is not supported for
                 // protocols that do not use URI."
 #pragma warning disable SYSLIB0014
-                return _servicePoint ??= ServicePointManager.FindServicePoint(new Uri("mailto:" + _host + ":" + _port));
+                return _servicePoint ??= ServicePointManager.FindServicePoint(new Uri($"mailto:{_host}:{_port}"));
 #pragma warning restore SYSLIB0014
             }
         }
diff --git a/src/libraries/System.Net.Requests/src/System/Net/HttpWebRequest.cs b/src/libraries/System.Net.Requests/src/System/Net/HttpWebRequest.cs
index 22f1a26abc01..066818b56f58 100644
--- a/src/libraries/System.Net.Requests/src/System/Net/HttpWebRequest.cs
+++ b/src/libraries/System.Net.Requests/src/System/Net/HttpWebRequest.cs
@@ -352,7 +352,7 @@ public string Host
                 Uri hostUri = _hostUri ?? Address;
                 return (_hostUri == null || !_hostHasPort) && Address.IsDefaultPort ?
                     hostUri.Host :
-                    hostUri.Host + ":" + hostUri.Port;
+                    $"{hostUri.Host}:{hostUri.Port}";
             }
             set
             {
diff --git a/src/libraries/System.Net.ServicePoint/src/System/Net/ServicePointManager.cs b/src/libraries/System.Net.ServicePoint/src/System/Net/ServicePointManager.cs
index 29b6f36532d0..fc25568015f9 100644
--- a/src/libraries/System.Net.ServicePoint/src/System/Net/ServicePointManager.cs
+++ b/src/libraries/System.Net.ServicePoint/src/System/Net/ServicePointManager.cs
@@ -197,8 +197,8 @@ private static bool ProxyAddressIfNecessary(ref Uri address, IWebProxy? proxy)
         }
 
         private static string MakeQueryString(Uri address) => address.IsDefaultPort ?
-            address.Scheme + "://" + address.DnsSafeHost :
-            address.Scheme + "://" + address.DnsSafeHost + ":" + address.Port.ToString();
+            $"{address.Scheme}://{address.DnsSafeHost}" :
+            $"{address.Scheme}://{address.DnsSafeHost}:{address.Port}";
 
         private static string MakeQueryString(Uri address, bool isProxy)
         {
diff --git a/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/ActivityTracker.cs b/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/ActivityTracker.cs
index 9b79bea9d0d0..52212d2c9512 100644
--- a/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/ActivityTracker.cs
+++ b/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/ActivityTracker.cs
@@ -264,7 +264,7 @@ private static string NormalizeActivityName(string providerName, string activity
             }
             else if (task != 0)
             {
-                return providerName + "task" + task.ToString();
+                return $"{providerName}task{task}";
             }
             else
             {
diff --git a/src/libraries/System.Reflection.DispatchProxy/src/System/Reflection/DispatchProxyGenerator.cs b/src/libraries/System.Reflection.DispatchProxy/src/System/Reflection/DispatchProxyGenerator.cs
index 0ed13300da89..a021153da1a5 100644
--- a/src/libraries/System.Reflection.DispatchProxy/src/System/Reflection/DispatchProxyGenerator.cs
+++ b/src/libraries/System.Reflection.DispatchProxy/src/System/Reflection/DispatchProxyGenerator.cs
@@ -220,7 +220,7 @@ public ProxyAssembly(AssemblyLoadContext alc)
                 [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicParameterlessConstructor)] Type proxyBaseType)
             {
                 int nextId = Interlocked.Increment(ref _typeId);
-                TypeBuilder tb = _mb.DefineType(name + "_" + nextId, TypeAttributes.Public, proxyBaseType);
+                TypeBuilder tb = _mb.DefineType($"{name}_{nextId}", TypeAttributes.Public, proxyBaseType);
                 return new ProxyBuilder(this, tb, proxyBaseType);
             }