What is the general difference between methods and types in ASP.NET?

Question

I am creating an online app, which required some C# code. So I created a new file name: User.cs, in that file I am having this code:

public class UserProperties {
    public string hasPermission (string permission) {
        // get the permissions of the user
        var db = Database.Open("VMS");
        var roles = db.Query("SELECT * FROM webpages_UsersInRoles 
        WHERE UserId =@0", WebSecurity.CurrentUserId);
        // Get the Role Id
        var getRole = "";
        foreach (var row in roles) {
            getRole = row.RoleId.ToString();
        }
        // Get the permission ID
        var permissions = db.Query("SELECT * FROM Permissions WHERE 
        LOWER(Permission_Name) = LOWER(@0)", permission);
        var permissionId = "";
        foreach (var row in permissions) {
            permissionId = row.Permission_Id.ToString();
        }
        // Now get the rolePermissions
        var role_permissions = db.Query("SELECT * FROM Role_Permissions 
        WHERE Role_Id =@0 AND Permission_Id =@1", getRole, permissionId);
        if(role_permissions.Count() == 0) {
            return "Not Allowed.";
        } else {
            return "Yes, full permission.";
        }
    }
}

This code would look for the user's permissions and then return a value. But its not happening. When I try to execute it:

@{ 
  new UserProperties.hasPermission("Create_Page");
}

It gives me an exception of:

CS0118: 'User.hasPermission(string)' is a 'method' but is used like a 'type'

I am not sure how am I using it as a type?

Answer 1

You need to use:

new UserProperties().hasPermission("Create_Page")

alternatively, you could make hasPermission static, then you won't need to create an instace

public static string hasPermission (string permission) { ... }

@{ 
  UserProperties.hasPermission("Create_Page");
}

Answer 2

The first line your code:

public class UserProperties

Defines a (object) Type.

The next line you declare an instance method.

public string hasPermission (string permission)

Unless you create an instance of UserProperties..

var userProperties = new UserProperties();

You can't call hasPermission() .

You could alternatively (not recommended) create a static method.

public static string hasPermission (string permission)

MSDN Docs 10.5.2 - Static and instance methods

Answer 3

All you need to do is add parentheses:

@{ 
  new UserProperties().hasPermission("Create_Page");
}

new UserProperties() creates an instance of the UserProperties class, which you then call the hasPermission method on.

If hasPermission were defined as static then your syntax would be valid (you don't need an instance to call the method on).

Answer 4

u will have to create an instance of UserProperties.

var up = new UserProperties();
up.hasPermission("Create_Page");

or just

new UserProperties().hasPermission("Create_Page");