C# Member 'System.Char[] System.String::ToCharArray()' is declared in another module and needs to be imported in Mono.Cecil

Question

I use Mono.Cecil to encrypt my strings in my assemblies.

but in

myAssemblyDefinition.Write(myAssemblyPath);

I get an error:

Member 'System.Char[] System.String::ToCharArray()' is declared in another module and needs to be imported

I tried to import String.ToCharArray method with all these lines:

myAssemblyDefinition.MainModule.Import(stringTypeReference.Resolve());
myAssemblyDefinition.MainModule.Import(stringTypeReference.Resolve().Module.Types.Where(x => x.Name == "String").First());
MethodDefinition toCharArrayMethod = stringTypeReference.Resolve().Module.Types.Where(x => x.Name == "String").First().Methods.Where(x => x.Name == "ToCharArray").First();
myAssemblyDefinition.MainModule.Import(toCharArrayMethod);
myAssemblyDefinition.MainModule.Import(typeof(System.String));

but my problem still exists. I used ToCharArray method for inject decryptMethod to my assembly. Can anybody help to me to solve this or is there a sample code to encrypt string for obfuscating with Mono.Cecil 0.9.5 version?

Answer 1

If your target assembly's runtime version is same with your injection code's runtime version. Try following lines.

var toCharArray =
 asm.MainModule.Import(typeof(string).GetMethod("ToCharArray", new Type[] { }));
proccer.Emit(OpCodes.Callvirt, toCharArray);