c#之SQL Server 的输出参数未打印到 Web 表单

我有一个存储过程

create proc spAddEmployees   
@Name varchar(50),   
@Gender varchar(10),   
@Salary int,   
@EmployeeId int out   
as   
begin   
insert into tblEmployees values (@Name, @Gender, @Salary)   
select EmployeeId = SCOPE_IDENTITY()   
end   

它有一个输出参数，告诉用户当前的 scope_identity 标记看起来像

<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent"> 
    <table style="border: 1px solid black; font-family:Arial"> 
    <tr> 
        <td> 
            Employee Name 
        </td> 
        <td> 
            <asp:TextBox ID="txtEmployeeName" runat="server"></asp:TextBox> 
        </td> 
    </tr>         
    <tr> 
        <td> 
            Gender 
        </td> 
        <td> 
            <asp:DropDownList ID="ddlGender" runat="server"> 
                <asp:ListItem>Male</asp:ListItem> 
                <asp:ListItem>Female</asp:ListItem> 
            </asp:DropDownList> 
        </td> 
    </tr>  
    <tr> 
        <td> 
            Salary 
        </td> 
        <td> 
            <asp:TextBox ID="txtSalary" runat="server"></asp:TextBox> 
        </td> 
    </tr>        
    <tr> 
        <td colspan="2"> 
            <asp:Button ID="btnSubmit" runat="server" Text="Submit"  
                onclick="btnSubmit_Click" /> 
        </td> 
    </tr>           
    <tr> 
        <td colspan="2"> 
            <asp:Label ID="lblMessage" runat="server"></asp:Label> 
        </td> 
    </tr>   
</table> 

以及背后的代码

 public partial class _Default : System.Web.UI.Page 
    { 
        protected void Page_Load(object sender, EventArgs e) 
        { 
 
        } 
 
        protected void btnSubmit_Click(object sender, EventArgs e) 
        { 
            //read from the config file so you don't have to hardcode the connection string 
            string cs = ConfigurationManager.ConnectionStrings["dbcs"].ConnectionString; 
            //when you use the using statement the database connection is automatically closed for you 
            using(SqlConnection con = new SqlConnection(cs)) 
            { 
                SqlCommand cmd = new SqlCommand("spAddEmployees", con); 
 
                cmd.CommandType = CommandType.StoredProcedure; 
 
 
                cmd.Parameters.AddWithValue("@Name", txtEmployeeName.Text); 
                cmd.Parameters.AddWithValue("@Gender",ddlGender.SelectedValue); 
                cmd.Parameters.AddWithValue("@Salary", txtSalary.Text); 
 
 
                SqlParameter outputParmeter = new SqlParameter(); 
 
                outputParmeter.ParameterName = "@EmployeeId"; 
 
                outputParmeter.SqlDbType = SqlDbType.Int; 
                outputParmeter.Direction = ParameterDirection.Output; 
 
                cmd.Parameters.Add(outputParmeter); 
 
                con.Open(); 
                cmd.ExecuteNonQuery(); 
 
                string EmpId = outputParmeter.Value.ToString(); 
                lblMessage.Text = "Employee Id = " + EmpId;     
 
 
            } 
 
        } 
    } 

这个程序应该向 tblEmployees 表中添加一个新行，然后将存储过程的输出参数输出给用户。单击按钮时，它会运行并将该行添加到数字中，但输出参数不会打印到屏幕上。想法？

请您参考如下方法:

也许:

select EmployeeId = SCOPE_IDENTITY()  

在存储过程中应该是:

select @EmployeeId = SCOPE_IDENTITY()