我正在开始编写网站代码,目前正在创建用户创建页面。所有验证工作正常,但我不确定将什么放入 checkUsername 方法以验证用户名不存在。下面是我的 ASP.NET 代码。
<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
<p>
<asp:ValidationSummary ID="ValidationSummary1" runat="server" HeaderText="There were errors on the page:" />
</p>
<p>
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="username" ErrorMessage="Username is required."> *</asp:RequiredFieldValidator>
Enter Username <asp:TextBox ID="username" runat="server"></asp:TextBox>
<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ControlToValidate="username" ErrorMessage="Username must be 4-10 letters or numbers." ValidationExpression="[a-zA-Z0-9]{4,10}" />
<asp:CustomValidator ID="CustomValidator1" runat="server" controltovalidate="username" errormessage="Username is already in use." OnServerValidate="checkUsername" />
</p>
<p>
Enter Password <asp:TextBox ID="entPWD" runat="server" TextMode="Password"></asp:TextBox>
<asp:RegularExpressionValidator ID="RegularExpressionValidator2" runat="server" display="dynamic" ControlToValidate="entPWD" ErrorMessage="Password must contain one of the following: @#$%^&*/." ValidationExpression=".*[@#$%^&*/].*" />
<asp:RegularExpressionValidator ID="RegularExpressionValidator3" runat="server" display="dynamic" ControlToValidate="entPWD" ErrorMessage="Password must be 6-12 characters." ValidationExpression="[^\s]{6,12}" />
</p>
<p>
Confirm Password <asp:TextBox ID="confPWD" runat="server" TextMode="Password"></asp:TextBox>
<asp:CompareValidator ID="CompareValidator1" runat="server" ControlToValidate="entPWD" ControlToCompare="confPWD" ErrorMessage="Passwords do not match." />
</p>
<asp:Button type="submit" ID="Button1" runat="server" Text="Submit" />
</asp:Content>
这是我的代码背后:
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
private bool checkUsername(string username)
{
string connString = "Data Source=serveraddress;Initial Catalog=database;User Id=username;Password=password;";
string cmdText = "SELECT COUNT(*) FROM igs_users WHERE username = @username";
using(SqlConnection conn = new SqlConnection(connString))
{
conn.Open();
using(SqlCommand cmd = new SqlCommand(cmdText, conn))
{
cmd.Parameters.AddWithValue("@username", username);
int count = (int)cmd.ExecuteScalar();
return (count > 0);
}
}
}
}
当我运行代码时,我收到以下错误消息:
Compiler Error Message: CS1061: 'ASP.default_aspx' does not contain a definition for 'checkUsername' and no extension method 'checkUsername' accepting a first argument of type 'ASP.default_aspx' could be found (are you missing a using directive or an assembly reference?)
不知道我哪里出错了。我有使用 System.Data.SqlClient; 在后面的代码中,还添加了对 system.data.dll 的引用。
任何帮助,将不胜感激!