表預期已經存在

Question

ALTER PROCEDURE tableuser 
    -- Add the parameters for the stored procedure here 
    @userName varchar(50) 
AS 
IF EXISTS(SELECT 'True' FROM tbl_user WHERE userName = @userName) 
BEGIN 
    --This means it exists, return it to ASP and tell us 
    SELECT 'This record already exists!' 
END 
ELSE 
BEGIN 
    --This means the record isn't in there already, let's go ahead and add it 
    SELECT 'Record Added' 
    INSERT into tbl_user(userName) VALUES(@username) 
END 

這是我在SQL Server Management Studio代碼和下面的參數是C＃代碼：

protected void Button1_Click(object sender, EventArgs e) 
{ 
    SqlCommand cmd = new SqlCommand("tableuser", conn); 
    conn.Open(); 
    SqlParameter param = new SqlParameter(); 
    cmd.Parameters.AddWithValue("@userName", uname.Text); 
    param.Value = uname.Text; 

    cmd.Parameters.Add(param); 

    SqlDataReader reader = cmd.ExecuteReader(); 

    if (reader.HasRows) 
    { 
     Response.Write("Username exists"); 
    } 
    else 
    { 
     cmd.Parameters.AddWithValue("@userName", uname.Text); 
     cmd.CommandType = System.Data.CommandType.StoredProcedure; 
     conn.Open(); 
     cmd.ExecuteNonQuery(); 
     Response.Write("Successfully saved...!!!"); 
     conn.Close(); 
    } 
} 

}

的錯誤出現是：過程或函數' tableuser'需要參數'@userName'，它沒有提供。

Answer 1

這應該工作：

conn.Open(); 
var cmd = new SqlCommand("tableuser", conn); 
cmd.CommandType = CommandType.StoredProcedure; 
cmd.Parameters.AddWithValue("@userName", uname.Text); 

var rdr = cmd.ExecuteReader(); 

rdr.Read(); 
Response.Write(rdr.GetString(0)); 
conn.Close();