Issue while getting the type of a class

Question

I am reading a app.config entry

  <add key="ClassNameSpace.ClassName" value="http://xxxx/xxx.asmx"/>

And I am trying to get the type for the key

  var section = configuration.GetSection(sectionKey.ToString());
  var appSettings = section as AppSettingsSection;
  if (appSettings == null) continue;

  foreach (var key in appSettings.Settings.AllKeys)
  {
      System.Type type = System.Type.GetType(typeof(key).AssemblyQualifiedName);
      var webService = new SecureWebService<type>().Service;
  }

But I am getting below error

'key' is a variable but is used like a type

Any idea to solve this issue

You can not call `typeof` with a variable, you need to call it with a Type (thats what the warning is trying to tell you) typeof(int) would be valid. You can call GetType with the key to get a type instance. — quadroid, Sep 19 '19 at 05:48
Nobody ever reads exception messages :( _"'key' is a variable but is used like a type"_ means that `key` is a variable, but you use it like a type in `typeof(key)` — vasily.sib, Sep 19 '19 at 05:50
The type of that key is probably just "String". I think you want the value of that key to get the new type — Hans Keﬆing, Sep 19 '19 at 05:55
So your question is how to get Type by class name? https://stackoverflow.com/questions/11107536/convert-string-to-type-in-c-sharp — TimChang, Sep 19 '19 at 06:02

score 1 · Accepted Answer · 2019-09-19T07:29:17.203

1

typeof() returns the Type of a type (class, interface, struct...) in the sense of the type name used in the code text.

For a string representation of a type, you should use:

Type type = Type.GetType(key); // full qualified like "namespace.type"
var webService = Activator.CreateInstance(type); // default constructor

edited Sep 19 '19 at 07:29

answered Sep 19 '19 at 05:50

That would not return what the OP wants, it would return the type of the key name container, not the type name the key represents. `Type.GetType(key.ToString())` is more likely to yield the desired result. – fredrik Sep 19 '19 at 05:56
my guess is that OP wants to get `Type` by it's name. Like `"System.String"` -> `typeos(System.String)`, so just leave `System.Type.GetType(key)` – vasily.sib Sep 19 '19 at 05:57
Indeed, key.GetType() returns "System.String". I updated the answer. – Sep 19 '19 at 08:09

score 0 · Answer 2 · answered Sep 19 '19 at 06:06

GetType() returns a System.Typeobject of an object. typeof() returns a System.Type object of a datatype.

var section = configuration.GetSection(sectionKey.ToString());
var appSettings = section as AppSettingsSection;
if (appSettings == null) continue;

foreach (var key in appSettings.Settings.AllKeys)
{
    System.Type type = key.GetType();
    var webService = new SecureWebService<type>().Service;
}

Issue while getting the type of a class

2 Answers2