Role Management

The above code is interface that the user will be presented with when he tries to create a new role or delete role if no user assigned to that role. It also delete role if any user is assigned to it. Please note that when a role is deleted with the users in it, those users would not be deleted from other roles.

When the page is run, it presents the user with the set of existing roles in the listbox.

For that you need to add a page load event with the following code:-

protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
//Fetch all the avaiable roles from the database
LstBoxDBind();
}
}
void LstBoxDBind ()
{
//Assigning the Data Source to List Box
lstBoxRoles.DataSource = Roles.GetAllRoles();
//Binding the List Box
lstBoxRoles.DataBind();
}

Roles in a membership API which has a number of method implemented within it. We will describe them briefly as and when required. If you notice in the code above we have

Roles.GetAllRoles () methodà is used to fetch all the roles from the aspnet_Roles table within the aspnetdb database.

Once all the roles are returned, it is possible that admin would want to add a new role.

Role management’s Role API has a new method CreateRole which takes a single string parameter à Roles.CreateRole(txtBoxRole.Text);

It is likely that admin might try to add a role that already exists within the aspnet_Roles table and therefore this needs to be checked for before role is added to avoid redundant entries. For that we need to use RoleExists () method implemented within the role class. Roles.RoleExists (txtBoxRole.Text) is the method which checks to see if the role already exists in the table. It return a boolean value i.e. true or false.

This is what we are doing is piece of code below. On the button click of create role, it check to see if the role already exists. If it exists, a message is returned back to user prompting the same. In case it does not exist, it creates a new role using the CreateRole () method.

For that Add the following code to Create Role button:-

protected void btnCreate_Click(object sender, EventArgs e)
{
try
{
lblMessage.Text = String.Empty;
// Check is the Role exists
if (!Roles.RoleExists(txtBoxRole.Text))
{
// Create Role
Roles.CreateRole(txtBoxRole.Text);
// Bind the list box again after creating the role
LstBoxDBind ();
//Displaying the message for role creation
lblMessage.Visible = true;
lblMessage.Text = "Role : '" + Server.HtmlEncode(txtBoxRole.Text.ToString()) + "' created.";
txtBoxRole.Text = "";
}
else
{
lblMessage.Visible = true;
lblMessage.Text = "Role : '" + Server.HtmlEncode(txtBoxRole.Text.ToString()) + "' already exists.";
} 
}
catch (Exception ex)
{
lblMessage.Visible = true;
lblMessage.Text = ex.Message;
}
}

For deleting roles we have Role API offers following methods:-

This method would delete the role from the aspnet_Roles table in case there are not users assigned to this role. In case users are assigned to this role, then your job would be to remove the users from role and then delete the role. Note that there is difference when we remove users from a role in the fact that the users will be removed only from that specified role and not from the remaining roles.

Add the following piece of code to remove role button click event:-

protected void btnRemove_Click(object sender, EventArgs e)
{
try
{
// Setting the lable for message to invisible
string strRole = String.Empty;
lblMessage.Text = String.Empty;
lblMessage.Visible = true;
strRole = lstBoxRoles.SelectedItem.Value;
//Checking if there are users assigned to a role
if (Roles.GetUsersInRole(strRole).Length == 0)
{
//Deleting Role
Roles.DeleteRole(strRole);
lblMessage.Visible = true;
lblMessage.Text = "Role :'" + Server.HtmlEncode(strRole) + "' deleted.";
}
else
{
lblMessage.Visible = true;
lblMessage.Text = "There are users assigned to Role '" + Server.HtmlEncode(strRole) + "'. Select a role and click <b>Remove Role with Users</b> button to delete the role.";
// Setting the visibility of btnRemoveRoleWithUser to true
}
// Re-bind roles to ListBox.
LstBoxDBind ();
}
catch (Exception ex)
{
lblMessage.Visible = true;
lblMessage.Text = ex.Message;
}
}

If you noticed, we have used another method à Roles.GetUsersInRole(string strRole). This method is used to check if the users are contained in that role. If the length of the string is returned is 0, then we can delete the role using Roles.DeleteRole (strRole) method.

In case the length of the string returned is not zero, then we need to remove the users from that role and then delete the role.

Removing users from roles can use any one of the following construct à

Roles.RemoveUserFromRole (string uname, string rolename)

Roles.RemoveUserFromRoles (string uname, string rolenames ())

Roles.RemoveUsersFromRole (string unames (), string rolename)

Roles.RemoveUsersFromRoles (string unames (), string rolenames ())

In our code, we want to remove users from that role and then delete the role. Therefore, we would be using the third construct à

You can add the logic to the button " remove role with users" and embed the construct appropriately wherever applicable. And then delete the role using the Roles.DeleteRole (strRole); method

Managing Roles

Next we are going to discuss how to manage users and roles. That is, how to assign user to role and how to remove the user from role.

The source code for this page is :-

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<asp:DropDownList ID="cboUser" Style="z-index: 166; left: 392px; position: absolute; top: 168px" Runat="server" Width="150px" Height="18px" DataSourceID="SqlDataSource1" DataTextField="UserName" DataValueField="UserName" OnSelectedIndexChanged="cboUser_SelectedIndexChanged" AutoPostBack="True" OnDataBound="cboUser_DataBound">
</asp:DropDownList>
<asp:Button ID="BtnDeleteRoles" Style="z-index: 172; left: 552px; position: absolute; top: 208px"
Runat="server" Height="24px" Width="131px" Text="Delete Roles" OnClick="btnDeleteRoles_Click" />
&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp; &nbsp;
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:aspnetdbConnectionString %>"
SelectCommand="SELECT * FROM [vw_aspnet_Users]"></asp:SqlDataSource>
<asp:Label ID="lblUser" Style="z-index: 170; left: 280px; position: absolute; top: 168px"
Runat="server" Text="Select a User" Font-Bold="True" Height="18px" Width="99px"></asp:Label>
<asp:Label ID="lblExistingRole" Style="z-index: 171; left: 272px; position: absolute; top: 208px"
Runat="server" Text="Existing Roles" Font-Bold="True" Height="18px" Width="107px"></asp:Label><asp:Label ID="lblAllRoles" Style="z-index: 171; left: 272px; position: absolute; top: 344px"
Runat="server" Text="Available Roles" Font-Bold="True" Height="18px" Width="107px"></asp:Label>
<asp:Button ID="btnAddRole" Style="z-index: 173; left: 552px; position: absolute; top: 344px"
Runat="server" Height="24px" Width="131px" Text="Add Role" OnClick="btnAddRoles_Click" />
<asp:Label ID="lblMessage" Style="z-index: 178; left: 440px; position: absolute; top: 464px"
Runat="server" Visible="False"></asp:Label>
<asp:ListBox ID="lstBoxExistingRoles" Style="z-index: 180; left: 392px; position: absolute;
top: 208px" Runat="server" Height="100px" Width="150px" SelectionMode="Multiple">
</asp:ListBox> &nbsp;
<asp:ListBox ID="lstBoxAllRoles" Style="z-index: 175; left: 392px; position: absolute; top: 344px" Runat="server" Height="100px" Width="150px" SelectionMode="Multiple" >
</asp:ListBox> &nbsp;&nbsp;&nbsp;
</form>
</body>
</html>