C# SqlParameter 使用

                //System.Data.SqlClient.SqlParameter[] sqlParameters = new System.Data.SqlClient.SqlParameter[]{ };
    System.Data.SqlClient.SqlParameter[] sqlParameters = new System.Data.SqlClient.SqlParameter[] { null, null };
                //sqlParameters[0] = new System.Data.SqlClient.SqlParameter("@name","123");

                System.Data.SqlClient.SqlParameter sp = new System.Data.SqlClient.SqlParameter("@name", "Pudding");

                SQLHelper.ExecuteScalar(CommandType.Text, "select count(*) from xx where 姓名='@Name' and 电话='@tel'", sp); --不能带引号 
 object select_count = SQLHelper.ExecuteScalar(CommandType.Text, "select count(*) from xx where 姓名=@Name and 电话=@Tel ", sqlParameters); --这是正确的

System.Data.SqlClient.SqlParameter[] sqlParameters = new System.Data.SqlClient.SqlParameter[] {
new System.Data.SqlClient.SqlParameter("@Name", Name),
new System.Data.SqlClient.SqlParameter("@Tel", Tel)
};

通过遍历ht  返回一个数组

System.Data.SqlClient.SqlParameter[] sqlParameters

        private static SqlParameter[] GetParameter(Hashtable ht)
        {
            SqlParameter[] parameters = new SqlParameter[ht.Count];
            int i = ;
            foreach (string key in ht.Keys)
            {
                parameters[i] = new SqlParameter("@" + key, ht[key]);
                i++;
            }
            return parameters;
        }