mcs/class/System/System.Configuration/AppSettingsReader.cs

   1 //
   2 // System.Configuration.AppSettingsReader
   3 //
   4 // Authors:
   5 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   6 //
   7 // (C) 2002 Ximian, Inc (http://www.ximian.com)
   8 //
   9
  10 using System.Reflection;
  11 using System.Collections.Specialized;
  12
  13 namespace System.Configuration
  14 {
  15         public class AppSettingsReader
  16         {
  17                 NameValueCollection appSettings;
  18
  19                 public AppSettingsReader ()
  20                 {
  21                         appSettings = ConfigurationSettings.AppSettings;
  22                 }
  23
  24                 public object GetValue (string key, Type type)
  25                 {
  26                         if (key == null)
  27                                 throw new ArgumentNullException ("key");
  28
  29                         if (type == null)
  30                                 throw new ArgumentNullException ("type");
  31
  32                         string value = appSettings [key];
  33                         if (value == null)
  34                                 throw new InvalidOperationException ("'" + key + "' could not be found.");
  35
  36                         if (type == typeof (string))
  37                                 return value;
  38
  39                         MethodInfo parse = type.GetMethod ("Parse", new Type [] {typeof (string)});
  40                         if (parse == null)
  41                                 throw new InvalidOperationException ("Type " + type + " does not have a Parse method");
  42
  43                         object result = null;
  44                         try {
  45                                 result = parse.Invoke (null, new object [] {value});
  46                         } catch (Exception e) {
  47                                 throw new InvalidOperationException ("Parse error.", e);
  48                         }
  49
  50                         return result;
  51                 }
  52         }
  53 }
  54