查询参数类：SQLServer

 /// <summary>
/// 查询参数生成基类
/// </summary>
public class SqlParameterProvider
{
    /// <summary>
    /// 参数集合
    /// </summary>
    private List<DbParameter> Params;

    /// <summary>
    /// 构造函数
    /// </summary>
    public SqlParameterProvider()
    {
        Params = new List<DbParameter>();
    }



  
    /// <summary>
    /// 获得参数集合
    /// </summary>
    /// <returns></returns>
    public DbParameter[] GetParms()
    {
        return Params.ToArray(); ;
    }

    /// <summary>
    /// 更改查询参数的值
    /// </summary>
    /// <param name="ParamName">要更改的查询参数名称</param>
    /// <param name="Value">新的参数值</param>
    public void SetParmValue(string ParamName, object Value)
    {
        var v = Params.Where(p => p.ParameterName == ParamName).FirstOrDefault();
        if (v != null)
            v.Value = Value;
    }


    /// <summary>
    /// 返回键值对参数 键：参数名，值：参数值
    /// </summary>
    /// <returns></returns>
    public Dictionary<string, object> GetParmArrary()
    {
        return null;
    }


    /// <summary>
    /// 获取参数值
    /// </summary>
    /// <typeparam name="T">返回类型</typeparam>
    /// <param name="ParameterName">参数名</param>
    /// <returns></returns>
    public T GetParamValue<T>(string ParameterName)
    {
        try
        {
            foreach (DbParameter param in Params)
            {
                if (param.ParameterName == ParameterName)
                {
                    return (T)param.Value;
                }
            }
            return default(T);
        }
        catch /*(Exception ex)*/
        {
            return default(T);
        }
    }


    public void AddParameter(string parameterName, object value)
    {
        SqlParameter parm = new SqlParameter(parameterName, value);
        Params.Add(parm);
    }
    public void AddParameter(string parameterName, SqlDbType dbType, object value)
    {
        SqlParameter parm = new SqlParameter(parameterName, dbType);
        parm.Value = value;
        Params.Add(parm);
    }

    public void AddParameter(string parameterName, SqlDbType dbType, int size, object value)
    {
        SqlParameter parm = new SqlParameter(parameterName, dbType, size);
        parm.Value = value;
        Params.Add(parm);
    }
    public void AddParameter(string parameterName, SqlDbType dbType, int size, object value, ParameterDirection direction)
    {
        SqlParameter parm = new SqlParameter(parameterName, dbType, size);
        parm.Value = value;
        parm.Direction = direction;
        Params.Add(parm);
    }
    public void AddParameter(string parameterName, SqlDbType dbType, int size, object value, string sourceColumn)
    {
        SqlParameter parm = new SqlParameter(parameterName, dbType, size, sourceColumn);
        parm.Value = value;
        Params.Add(parm);
    }

}