Fix null or empty string encryption

Author: Eastrall

src/EntityFrameworkCore.DataEncryption/EntityFrameworkCore.DataEncryption.csproj

@@ -7,7 +7,7 @@
 		<AssemblyName>EntityFrameworkCore.DataEncryption</AssemblyName>
 		<RootNamespace>Microsoft.EntityFrameworkCore.DataEncryption</RootNamespace>
 		<IsPackable>true</IsPackable>
-		<Version>4.0.0</Version>
+		<Version>4.0.1</Version>
 		<Authors>Filipe GOMES PEIXOTO</Authors>
 		<PackageId>EntityFrameworkCore.DataEncryption</PackageId>
 		<PackageProjectUrl>https://github.com/Eastrall/EntityFrameworkCore.DataEncryption</PackageProjectUrl>
@@ -20,7 +20,7 @@
 		<Copyright>Filipe GOMES PEIXOTO © 2019 - 2023</Copyright>
 		<Description>A plugin for Microsoft.EntityFrameworkCore to add support of encrypted fields using built-in or custom encryption providers.</Description>
 		<PackageLicenseFile>LICENSE</PackageLicenseFile>
-		<PackageReleaseNotes>https://github.com/Eastrall/EntityFrameworkCore.DataEncryption/releases/tag/v4.0.0</PackageReleaseNotes>
+		<PackageReleaseNotes>https://github.com/Eastrall/EntityFrameworkCore.DataEncryption/releases/tag/v4.0.1</PackageReleaseNotes>
 		<PackageReadmeFile>README.md</PackageReadmeFile>
 	</PropertyGroup>
 

src/EntityFrameworkCore.DataEncryption/Internal/EncryptionConverter.cs

@@ -30,13 +30,18 @@ private static TOutput Encrypt<TInput, TOutput>(TInput input, IEncryptionProvide
     {
         byte[] inputData = input switch
         {
-            string => Encoding.UTF8.GetBytes(input.ToString()),
+            string => !string.IsNullOrEmpty(input.ToString()) ? Encoding.UTF8.GetBytes(input.ToString()) : null,
             byte[] => input as byte[],
             _ => null,
         };
 
         byte[] encryptedRawBytes = encryptionProvider.Encrypt(inputData);
 
+        if (encryptedRawBytes is null)
+        {
+            return default;
+        }
+
         object encryptedData = storageFormat switch
         {
             StorageFormat.Default or StorageFormat.Base64 => Convert.ToBase64String(encryptedRawBytes),