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ResourceManager Constructor (String, Assembly, Type)

Initializes a new instance of the ResourceManager class that looks up resources contained in files with the specified root name in the given Assembly.

Namespace:  System.Resources
Assembly:  mscorlib (in mscorlib.dll)

public ResourceManager(
	string baseName,
	Assembly assembly,
	Type usingResourceSet


Type: System.String
The root name of the resource file without its extension and along with any fully qualified namespace name. For example, the root name for the resource file named "MyApplication.MyResource.en-US.resources" is "MyApplication.MyResource".
Type: System.Reflection.Assembly
The main assembly for the resources.
Type: System.Type
The type of the custom ResourceSet to use. If null, the default runtime ResourceSet object is used.


usingResourceset is not a derived class of ResourceSet.


The baseName or assembly parameter is null.

The individual resource files should be contained in satellite assemblies with the invariant culture's .resources file contained in the main assembly. A satellite assembly is assumed to contain resources for a single culture specified in that assembly's manifest, and are loaded as necessary.


To retrieve resources from .resources files directly instead of retrieving them from assemblies, you must call the CreateFileBasedResourceManager method instead to instantiate a ResourceManager object.

If the resource file identified by baseName cannot be found in assembly, the method instantiates a ResourceManager object, but the attempt to retrieve a specific resource throws an exception, typically a MissingManifestResourceException. For information about diagnosing the cause of the exception, see the "Handling MissingManifestResourceException and MissingSatelliteAssemblyException Exceptions" section of the ResourceManager class topic.

You can specify a ResourceSet implementation to be used. If you do not need a specific ResourceSet implementation but would like to use a custom resource file format, you should derive from the ResourceSet class, override GetDefaultReader and GetDefaultWriter, and pass that type to this constructor.


The usingResourceSet parameter is used to support your own resource format, and will commonly be null. This is different from the constructor that takes a Type only.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.