只是做笔记，没什么！！
复制代码 代码如下:
--创建测试表
CREATE TABLE [dbo].[Student](
[ID] [int] IDENTITY(1,1) NOT NULL PRIMARY KEY,
[Name] [nvarchar](20) NOT NULL DEFAULT (''),
[Age] [int] NOT NULL DEFAULT (0),
[Sex] [bit] NOT NULL DEFAULT (0),
[Address] [nvarchar](200) NOT NULL DEFAULT ('')
)
--比如是一个查询存储过程
Create PROC GetStudentByType
@type int =0, -- 1根据id查询, 2根据性别查询
@args XML -- 参数都写到这里吧
AS
BEGIN
DECLARE @id INT,@sex BIT
SET @id=@args.value('(args/id)[1]','int') --参数都可以写在这里，如果没有传过来，大不了是null值了，反正也用不到，没关系的
SET @sex =@args.value('(args/sex)[1]','bit')
IF(@type=1)
BEGIN
SELECT * FROM dbo.Student WHERE ID=@id
END
IF(@type=2)
BEGIN
SELECT * FROM dbo.Student WHERE Sex=@sex
END
END

参数写xml里感觉比用字符串要好很多，这样调用时参数就不好组织了，所以这里要有个帮助类XmlArgs
复制代码 代码如下:
public class XmlArgs
{
private string _strArgs = string.Empty;
private bool _isCreate = false;
private Dictionary<string, string> _args;
public string Args
{
get
{
if (!_isCreate)
{
_strArgs = _CreateArgs();
_isCreate = true;
}
return _strArgs;
}
}
public XmlArgs()
{
_args = new Dictionary<string, string>();
}
public void Add(string key, object value)
{
_args.Add(key, value.ToString());
_isCreate = false;
}
public void Remove(string key)
{
_args.Remove(key);
_isCreate = false;
}
public void Clear()
{
_args.Clear();
_isCreate = false;
}
private string _CreateArgs()
{
if (_args.Count == 0)
{
return string.Empty;
}
StringBuilder sb = new StringBuilder();
foreach (string key in _args.Keys)
{
sb.AppendFormat("<{0}>{1}</{0}>", key, _args[key]);
}
return sb.ToString();
}
}

调用：
复制代码 代码如下:
private void BindData()
{
XmlArgs args = new XmlArgs();
args.Add("id", 1);
System.Data.DataTable dt = GetStudentByType(1, args);
GridView1.DataShow(dt);
}
private System.Data.DataTable GetStudentByType(int type, XmlArgs args)
{
SqlHelper helper = new SqlHelper();
helper.Params.Add("type", type);
helper.Params.Add("args", args.Args);
System.Data.DataTable dt = helper.RunDataTable("GetStudentByType");
return dt;
}