public sealed class EnvironmentPermission : System.Security.CodeAccessPermission : IUnrestrictedPermission,
IBuiltInPermission {
// Public Constructors
public EnvironmentPermission(EnvironmentPermissionAccess flag, string pathList);
public EnvironmentPermission(PermissionState state);
// Public Instance Methods
public void AddPathList(EnvironmentPermissionAccess flag, string pathList);
public override IPermission Copy( );
// overrides CodeAccessPermission
public override void FromXml(System.Security.SecurityElement esd);
// overrides CodeAccessPermission
public string GetPathList(EnvironmentPermissionAccess flag);
public override IPermission Intersect(System.Security.IPermission target);
// overrides CodeAccessPermission
public override bool IsSubsetOf(System.Security.IPermission target);
// overrides CodeAccessPermission
public bool IsUnrestricted( );
// implements IUnrestrictedPermission
public void SetPathList(EnvironmentPermissionAccess flag, string pathList);
public override SecurityElement ToXml( );
// overrides CodeAccessPermission
public override IPermission Union(System.Security.IPermission other);
// overrides CodeAccessPermission
}
This code-access permission controls access to read and write
environment variables, as well as the ability to call certain members
of the System.Environment class. To create an
EnvironmentPermission object representing access
to a specific set of environment variables, pass a
semicolon-separated list of environment variable names to the object
constructor along with a value from the
EnvironmentPermissionAccess enumeration. The
EnvironmentPermissionAccess enumeration contains
values that represent the type of access granted to an environment
variable, such as permission to read or write.
The EnvironmentPermission class maintains separate
lists of environment variables with read access
(EnvironmentPermissionAccess.Read), and those with
write access (EnvironmentPermissionAccess.Write).
The EnvironmentPermission class does not treat the
EnvironmentPermissionAccess.AllAccess as a
separate value, and instead assigns independent read and write access
to environment variables assigned this access level.
The lists of accessible environment variables are managed using the
SetPathList( ) and AddPathList(
) methods, which both take values of the
EnvironmentPermissionAccess enumeration and a
semicolon-separated list of environment variable names as arguments.
SetPathList( ) replaces the existing list of
variables with the new set; its
EnvironmentPermissionAccess argument specifies
whether to replace the read or write list. AddPathList(
) grants access to the specified variables, adding them to
the existing list; its EnvironmentPermissionAccess
argument specifies which variable list to modify.
The GetPathList( ) method returns a semi-colon
separated list of environment variables that has access to the
specified type. GetPathList( ) accepts only the
EnvironmentPermissionAccess.Read or
EnvironmentPermissionAccess.Write values, and will
throw a System.ArgumentException if any other
values is specified.
System.Security.CodeAccessPermission(System.Security.IPermission,
System.Security.ISecurityEncodable,
System.Security.IStackWalk) 
