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SqlRoleProvider.DeleteRole(String, Boolean) Method

  • Reference

Definition

Namespace:
System.Web.Security
Assembly:
System.Web.dll

Removes a role from the role database.

public:
 override bool DeleteRole(System::String ^ roleName, bool throwOnPopulatedRole);
public override bool DeleteRole (string roleName, bool throwOnPopulatedRole);
override this.DeleteRole : string * bool -> bool
Public Overrides Function DeleteRole (roleName As String, throwOnPopulatedRole As Boolean) As Boolean

Parameters

roleName
String

The name of the role to delete.

throwOnPopulatedRole
Boolean

If true, throws an exception if roleName has one or more members.

Returns

Boolean

true if the role was successfully deleted; otherwise, false.

Exceptions

ArgumentNullException

roleName is null (Nothing in Visual Basic).

ArgumentException

roleName is an empty string or contains a comma.

-or-

roleName is longer than 256 characters.

ProviderException

roleName has one or more members and throwOnPopulatedRole is true.

-or-

An unknown error occurred while communicating with the database.

Examples

The following example deletes a role from the database. For an example of a Web.config file that enables role management, see SqlRoleProvider.


<%@ Page Language="C#" %>

<%@ Import Namespace="System.Web.Security" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  string[] rolesArray;

  public void Page_Load(object sender, EventArgs args)
  {
    if (!IsPostBack)
    {
      // Bind roles to ListBox.

      rolesArray = Roles.GetAllRoles();
      RolesListBox.DataSource = rolesArray;
      RolesListBox.DataBind();
    }
  }


  public void DeleteRole_OnClick(object sender, EventArgs args)
  {
    string delRole = "";

    try
    {
      delRole = RolesListBox.SelectedItem.Value;

      Roles.DeleteRole(delRole);

      Msg.Text = "Role '" + Server.HtmlEncode(delRole) + "' deleted.";


      // Re-bind roles to ListBox.

      rolesArray = Roles.GetAllRoles();
      RolesListBox.DataSource = rolesArray;
      RolesListBox.DataBind();
    }
    catch
    {
      Msg.Text = "Role '" + Server.HtmlEncode(delRole) + "' <u>not</u> deleted.";
    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
  <title>Sample: Delete Role</title>
</head>
<body>
  <form runat="server" id="PageForm">
    <h3>
      Delete Role</h3>
    <asp:Label ID="Msg" ForeColor="maroon" runat="server" /><br />
    <table border="0">
      <tr>
        <td valign="top">
          Delete Role:</td>
        <td valign="top">
          <asp:ListBox ID="RolesListBox" runat="server" Rows="8" /></td>
        <td valign="top">
          <asp:Button Text="Delete Role" ID="DeleteRoleButton" runat="server" OnClick="DeleteRole_OnClick" /></td>
      </tr>
    </table>
  </form>
</body>
</html>


<%@ Page Language="VB" %>

<%@ Import Namespace="System.Web.Security" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  Dim rolesArray() As String

  Public Sub Page_Load(ByVal sender As Object, ByVal args As EventArgs)

    If Not IsPostBack Then
      ' Bind roles to ListBox.

      rolesArray = Roles.GetAllRoles()
      RolesListBox.DataSource = rolesArray
      RolesListBox.DataBind()
    End If

  End Sub


  Public Sub DeleteRole_OnClick(ByVal sender As Object, ByVal args As EventArgs)

    Dim delRole As String

    Try
      delRole = RolesListBox.SelectedItem.Value

      Roles.DeleteRole(delRole)

      Msg.Text = "Role '" & Server.HtmlEncode(delRole) & "' deleted."

      ' Re-bind roles to ListBox.

      rolesArray = Roles.GetAllRoles()
      RolesListBox.DataSource = rolesArray
      RolesListBox.DataBind()
    Catch
      Msg.Text = "Role '" & Server.HtmlEncode(delRole) & "' <u>not</u> deleted."
    End Try

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
  <title>Sample: Delete Role</title>
</head>
<body>
  <form runat="server" id="PageForm">
    <h3>
      Delete Role</h3>
    <asp:Label ID="Msg" ForeColor="maroon" runat="server" /><br />
    <table border="0">
      <tr>
        <td valign="top">
          Delete Role:</td>
        <td valign="top">
          <asp:ListBox ID="RolesListBox" runat="server" Rows="8" /></td>
        <td valign="top">
          <asp:Button Text="Delete Role" ID="DeleteRoleButton" runat="server" OnClick="DeleteRole_OnClick" /></td>
      </tr>
    </table>
  </form>
</body>
</html>

Remarks

The DeleteRole method is called by the Roles class to delete a role from the SQL Server database specified in the ASP.NET application's configuration file (Web.config). When a role is deleted, the list of users associated with that role is also deleted from the database. The user information in the database is not affected.

If throwOnPopulatedRole is true, then an exception will be thrown and the role will not be deleted if the role identified by the roleName parameter has one or more members. If throwOnPopulatedRole is false, then the role will be deleted whether it is empty or not.

Applies to

See also