如何遍历一组用户并将其添加到C＃中

Question

I have some code that sets up a user:

const string name = "joe";
const string password = "abc";
const string roleName = "def";

After this there is a lot of C# code to add the user:

var role = RoleManager.FindByName(roleName);
if (role == null) {
    role = new IdentityRole(roleName);
    var roleresult = RoleManager.Create(role);
}

var user = UserManager.FindByName(name);
if (user == null) {
    user = new ApplicationUser { UserName = name, Email = name };
    var result = UserManager.Create(user, password);
    result = UserManager.SetLockoutEnabled(user.Id, false);
}

// Add user admin to Role Admin if not already added
var rolesForUser = UserManager.GetRoles(user.Id);
if (!rolesForUser.Contains(role.Name)) {
    var result = UserManager.AddToRole(user.Id, role.Name);
}

What I need is to add four or five different users.
Is there a way I can put my users in an object and loop through this calling the adding code ?

Answer 1

There certainly is a way! But to do it properly, it will take a few steps to get there. First, create a small class to represent a "user". Here's one with a constructor and some auto-properties:

public class MyUser
{
    public MyUser(string name, string password, string roleName)
    {
        this.Name = name;
        this.Password = password;
        this.RoleName = roleName;
    }
    public string Name { get; set; }
    public string Password { get; private set; }
    public string RoleName { get; set; }
}

^{Disclaimer : Don't call this class MyUser , come up with a much better name! This is for illustration only!}

Now, to put your users "in an object", you can create a List<T> object and add some new MyUser instances to it:

var newUsers = new List<MyUser>
{
    new MyUser("name1", "pwd1", "role1"),
    new MyUser("name2", "pwd2", "role2"),
    etc.
};

This creates the list and immediately adds the users to it using collection initializer syntax. You can also do it the long way if you need to do it in a loop:

var newUsers = new List<MyUser>();
newUsers.Add(new MyUser("name1", "pwd1", "role1"));
newUsers.Add(new MyUser("name2", "pwd2", "role2"));
// etc.

Next, having your "create user" code in a function will help, but in one that takes a MyUser class as a parameter:

public void CreateUser(MyUser myUser)
{
    // A little protection
    if (myUser == null)
        throw new ArgumentNullException("user");

    var role = RoleManager.FindByName(myUser.RoleName);
    if (role == null) {
        role = new IdentityRole(myUser.RoleName);
        var roleresult = RoleManager.Create(role);
    }

    var user = UserManager.FindByName(myUser.Name);
    if (user == null) {
        user = new ApplicationUser { UserName = myUser.Name, Email = myUser.Name };
        var result = UserManager.Create(user, myUser.Password);
        result = UserManager.SetLockoutEnabled(user.Id, false);
    }

    // Add user admin to Role Admin if not already added
    var rolesForUser = UserManager.GetRoles(user.Id);
    if (!rolesForUser.Contains(role.Name)) {
        var result = UserManager.AddToRole(user.Id, role.Name);
    }
}

Now, to finally create the users, you just have to loop through your list of MyUser s and pass them over to the CreateUser() function:

foreach (var user in newUsers)
{
    CreateUser(user);
}

Of course, you'll want to incorporate try/catch blocks where necessary, add proper validation, etc. This is just to illustrate how I would approach this.