Generates a random password of the specified length.
(in System.Web.dll)
Visual Basic (Declaration)
Public Shared Function GeneratePassword ( _
length As Integer, _
numberOfNonAlphanumericCharacters As Integer _
) As String
Dim length As Integer
Dim numberOfNonAlphanumericCharacters As Integer
Dim returnValue As String
returnValue = Membership.GeneratePassword(length, _
numberOfNonAlphanumericCharacters)
public static string GeneratePassword(
int length,
int numberOfNonAlphanumericCharacters
)
public:
static String^ GeneratePassword(
int length,
int numberOfNonAlphanumericCharacters
)
public static function GeneratePassword(
length : int,
numberOfNonAlphanumericCharacters : int
) : String
Parameters
- length
- Type: System..::.Int32
The number of characters in the generated password. The length must be between 1 and 128 characters.
- numberOfNonAlphanumericCharacters
- Type: System..::.Int32
The minimum number of punctuation characters in the generated password.
| Exception | Condition |
|---|
| ArgumentException |
length is less than 1 or greater than 128 -or-
numberOfNonAlphanumericCharacters is less than 0 or greater than length. |
The GeneratePassword method is used to generate a random password and is most commonly used by the ResetPassword method implemented by a membership provider to reset the password for a user to a new, temporary password.
The generated password only contains alphanumeric characters and the following punctuation marks: !@#$%^&*()_-+=[{]};:<>|./?. No hidden or non-printable control characters are included in the generated password.
.gif) Note: |
|---|
The random password created by the GeneratePassword method is not guaranteed to pass the regular expression in the PasswordStrengthRegularExpression property. However, the random password will meet the criteria established by the MinRequiredPasswordLength property and the numberOfNonAlphanumericCharacters parameter. |
The following code example creates a new membership user and uses the GeneratePassword method to initialize the password for the new user to a random value, which is displayed to the user.
.gif) Security Note: |
|---|
This example contains a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview. |
<%@ 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">
Public Sub CreateUser_OnClick(sender As Object, args As EventArgs)
' Create a new 12-character password with 1 non-alphanumeric character.
Dim password As String = Membership.GeneratePassword(12, 1)
Try
' Create new user.
Dim newUser As MembershipUser = Membership.CreateUser(UsernameTextbox.Text, password, _
EmailTextbox.Text)
Msg.Text = "User <b>" & Server.HtmlEncode(UsernameTextbox.Text) & "</b> created. " & _
"Your temporary password is " & password & "."
Catch e As MembershipCreateUserException
Msg.Text = GetErrorMessage(e.StatusCode)
Catch e As HttpException
Msg.Text = e.Message
End Try
End Sub
Public Function GetErrorMessage(status As MembershipCreateStatus) As String
Select Case status
Case MembershipCreateStatus.DuplicateUserName
Return "Username already exists. Please enter a different user name."
Case MembershipCreateStatus.DuplicateEmail
Return "A username for that e-mail address already exists. Please enter a different e-mail address."
Case MembershipCreateStatus.InvalidPassword
Return "The password provided is invalid. Please enter a valid password value."
Case MembershipCreateStatus.InvalidEmail
Return "The e-mail address provided is invalid. Please check the value and try again."
Case MembershipCreateStatus.InvalidAnswer
Return "The password retrieval answer provided is invalid. Please check the value and try again."
Case MembershipCreateStatus.InvalidQuestion
Return "The password retrieval question provided is invalid. Please check the value and try again."
Case MembershipCreateStatus.ProviderError
Return "The authentication provider Returned an error. Please verify your entry and try again. If the problem persists, please contact your system administrator."
Case MembershipCreateStatus.UserRejected
Return "The user creation request has been canceled. Please verify your entry and try again. If the problem persists, please contact your system administrator."
Case Else
Return "An unknown error occurred. Please verify your entry and try again. If the problem persists, please contact your system administrator."
End Select
End Function
</script>
<html >
<head>
<title>Create User</title>
</head>
<body>
<form id="form1" runat="server">
<h3>Create New User</h3>
<asp:Label id="Msg" ForeColor="maroon" runat="server" /><br />
<table cellpadding="3" border="0">
<tr>
<td>Username:</td>
<td><asp:Textbox id="UsernameTextbox" runat="server" /></td>
<td><asp:RequiredFieldValidator id="UsernameRequiredValidator" runat="server"
ControlToValidate="UserNameTextbox" ForeColor="red"
Display="Static" ErrorMessage="Required" /></td>
</tr>
<tr>
<td>Email Address:</td>
<td><asp:Textbox id="EmailTextbox" runat="server" /></td>
<td><asp:RequiredFieldValidator id="EmailRequiredValidator" runat="server"
ControlToValidate="EmailTextbox" ForeColor="red"
Display="Static" ErrorMessage="Required" /></td>
</tr>
<tr>
<td></td>
<td><asp:Button id="CreateUserButton" Text="Create User" OnClick="CreateUser_OnClick" runat="server" /></td>
</tr>
</table>
</form>
</body>
</html>
<%@ 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">
public void CreateUser_OnClick(object sender, EventArgs args)
{
// Generate a new 12-character password with 1 non-alphanumeric character.
string password = Membership.GeneratePassword(12, 1);
try
{
// Create new user.
MembershipUser newUser = Membership.CreateUser(UsernameTextbox.Text, password,
EmailTextbox.Text);
Msg.Text = "User <b>" + Server.HtmlEncode(UsernameTextbox.Text) + "</b> created. " +
"Your temporary password is " + password + ".";
}
catch (MembershipCreateUserException e)
{
Msg.Text = GetErrorMessage(e.StatusCode);
}
catch (HttpException e)
{
Msg.Text = e.Message;
}
}
public string GetErrorMessage(MembershipCreateStatus status)
{
switch (status)
{
case MembershipCreateStatus.DuplicateUserName:
return "Username already exists. Please enter a different user name.";
case MembershipCreateStatus.DuplicateEmail:
return "A username for that e-mail address already exists. Please enter a different e-mail address.";
case MembershipCreateStatus.InvalidPassword:
return "The password provided is invalid. Please enter a valid password value.";
case MembershipCreateStatus.InvalidEmail:
return "The e-mail address provided is invalid. Please check the value and try again.";
case MembershipCreateStatus.InvalidAnswer:
return "The password retrieval answer provided is invalid. Please check the value and try again.";
case MembershipCreateStatus.InvalidQuestion:
return "The password retrieval question provided is invalid. Please check the value and try again.";
case MembershipCreateStatus.ProviderError:
return "The authentication provider returned an error. Please verify your entry and try again. If the problem persists, please contact your system administrator.";
case MembershipCreateStatus.UserRejected:
return "The user creation request has been canceled. Please verify your entry and try again. If the problem persists, please contact your system administrator.";
default:
return "An unknown error occurred. Please verify your entry and try again. If the problem persists, please contact your system administrator.";
}
}
</script>
<html >
<head>
<title>Create User</title>
</head>
<body>
<form id="form1" runat="server">
<h3>Create New User</h3>
<asp:Label id="Msg" ForeColor="maroon" runat="server" /><br />
<table cellpadding="3" border="0">
<tr>
<td>Username:</td>
<td><asp:Textbox id="UsernameTextbox" runat="server" /></td>
<td><asp:RequiredFieldValidator id="UsernameRequiredValidator" runat="server"
ControlToValidate="UserNameTextbox" ForeColor="red"
Display="Static" ErrorMessage="Required" /></td>
</tr>
<tr>
<td>Email Address:</td>
<td><asp:Textbox id="EmailTextbox" runat="server" /></td>
<td><asp:RequiredFieldValidator id="EmailRequiredValidator" runat="server"
ControlToValidate="EmailTextbox" ForeColor="red"
Display="Static" ErrorMessage="Required" /></td>
</tr>
<tr>
<td></td>
<td><asp:Button id="CreateUserButton" Text="Create User" OnClick="CreateUser_OnClick" runat="server" /></td>
</tr>
</table>
</form>
</body>
</html>
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
.NET Framework
Supported in: 3.5, 3.0, 2.0
Reference
Other Resources