[c#] Convert String to Type in C#

If I receive a string that contains the name of a class and I want to convert this string to a real type (the one in the string), how can I do this?

I tried

Type.GetType("System.Int32")

for example, it appears to work.

But when I try with my own object, it always returns null ...

I have no idea what will be in the string in advance so it's my only source for converting it to its real type.

Type.GetType("NameSpace.MyClasse");

Any idea?

If you really want to get the type by name you may use the following:

System.AppDomain.CurrentDomain.GetAssemblies().SelectMany(x => x.GetTypes()).First(x => x.Name == "theassembly");

Note that you can improve the performance of this drastically the more information you have about the type you're trying to load.

Try:

Type type = Type.GetType(inputString); //target type
object o = Activator.CreateInstance(type); // an instance of target type
YourType your = (YourType)o;

Jon Skeet is right as usually :)

Update: You can specify assembly containing target type in various ways, as Jon mentioned, or:

YourType your = (YourType)Activator.CreateInstance("AssemblyName", "NameSpace.MyClass");

use following LoadType method to use System.Reflection to load all registered(GAC) and referenced assemblies and check for typeName

public Type[] LoadType(string typeName)
{
    return LoadType(typeName, true);
}

public Type[] LoadType(string typeName, bool referenced)
{
    return LoadType(typeName, referenced, true);
}

private Type[] LoadType(string typeName, bool referenced, bool gac)
{
    //check for problematic work
    if (string.IsNullOrEmpty(typeName) || !referenced && !gac)
        return new Type[] { };

    Assembly currentAssembly = Assembly.GetExecutingAssembly();

    List<string> assemblyFullnames = new List<string>();
    List<Type> types = new List<Type>();

    if (referenced)
    {            //Check refrenced assemblies
        foreach (AssemblyName assemblyName in currentAssembly.GetReferencedAssemblies())
        {
            //Load method resolve refrenced loaded assembly
            Assembly assembly = Assembly.Load(assemblyName.FullName);

            //Check if type is exists in assembly
            var type = assembly.GetType(typeName, false, true);

            if (type != null && !assemblyFullnames.Contains(assembly.FullName))
            {
                types.Add(type);
                assemblyFullnames.Add(assembly.FullName);
            }
        }
    }

    if (gac)
    {
        //GAC files
        string gacPath = Environment.GetFolderPath(System.Environment.SpecialFolder.Windows) + "\\assembly";
        var files = GetGlobalAssemblyCacheFiles(gacPath);
        foreach (string file in files)
        {
            try
            {
                //reflection only
                Assembly assembly = Assembly.ReflectionOnlyLoadFrom(file);

                //Check if type is exists in assembly
                var type = assembly.GetType(typeName, false, true);

                if (type != null && !assemblyFullnames.Contains(assembly.FullName))
                {
                    types.Add(type);
                    assemblyFullnames.Add(assembly.FullName);
                }
            }
            catch
            {
                //your custom handling
            }
        }
    }

    return types.ToArray();
}

public static string[] GetGlobalAssemblyCacheFiles(string path)
{
    List<string> files = new List<string>();

    DirectoryInfo di = new DirectoryInfo(path);

    foreach (FileInfo fi in di.GetFiles("*.dll"))
    {
        files.Add(fi.FullName);
    }

    foreach (DirectoryInfo diChild in di.GetDirectories())
    {
        var files2 = GetGlobalAssemblyCacheFiles(diChild.FullName);
        files.AddRange(files2);
    }

    return files.ToArray();
}