常用代码

//添加连接
第一个<appSetting/>后添加<appSetting>
<add key="conString" value=""/>
</appSetting> 删除原来的<appSetting/>
//获取  
ConfigurationManager.AppSettings["conString"];
//打开连接
private static void OpenSqlCon()
{
if(sqlCon.State=Connection.Closed)
{
sqlCon.Open();
}
}
//关闭连接
private static void CloseSqlCon()
{
if(sqlCon.State=Connection.Open)
{
sqlCon.Close();
}
}
//执行sql语句返回一个DataSet
public static DataSet ExecSql(string sql)
{
try
{
OpenSqlCon();
sqlSet.Clear();
sqlDa=new SqlDataAdapter(sql,sqlCon);
sqlDa.Fill(sqlSet);
CloseSqlCon();
}
catch(Exception)
{
throw();
}
finally
{
CloseSqlCon();
}
return sqlSet;
}
//执行sql语句返回第一个单元格的数据
public static DataSet ExecReturnFirstCell(string sql)
{
try
{
OpenSqlCon();
sqlCmd=new SqlCommand(sql,sqlCon);
returnString=sqlCmd.ExecutScalar();
CloseSqlCon();
}
catch(Exception)
{
throw();
}
finally
{
CloseSqlCon();
sqlCmd.Dispose();
}
return returnString;
}
//插入数据和更新数据
public static DataSet ExecSql(string sql,string name,string content )
{
int i=0;
try
{
OpenSqlCon();
sqlCmd=new SqlCommand(sql,sqlCon);
sqlCmd.Paramters.Add('@name',SqlDbType.NChar).value=name;
sqlCmd.Paramters.Add('@content',SqlDbType.Text).value=content;
i=sqlCmd.ExectuNonQuery();
}
catch(Exception)
{
throw();
}
finally
{
CloseSqlCon();
sqlCmd.Dispose();
}
return i;
}
//删除数据
public static DataSet ExecSql(string sql,string id)
{
int i=0;
try
{
OpenSqlCon();
sqlCmd=new SqlCommand(sql,sqlCon);
sqlCmd.Paramters.Add('@id',SqlDbType.int).value=id;
i=sqlCmd.ExectuNonQuery();
}
catch(Exception)
{
throw();
}
finally
{
CloseSqlCon();
sqlCmd.Dispose();
}
return i;
}
//执行存储过程返回一个DataSet
//执行存储过程返回第一行第一列的数据

//防止恶意刷新(页面跳转,局部刷新,或者 验证玛.都可以解决这个问题)
Response.Redirect(Request.RawUrl );   

//取消默认的输入验证,即自动检查提交的文本中的恶意代码(可以提交html代码)
在web.config文件第一个System.web中添加
<pages validateRequest="false">
</Pages>
<%#Server.HtmlEncode(Eval("content").ToString())%>

//注释
#region
#endregion

//分页
 PagedDataSource ps = new PagedDataSource();
 ps.DataSource = dt.DefaultView ;
ps.AllowPaging=true;
ps.PageSize=5;
ps.CurrentPageIndex = ViewState["Page"];
ViewState["count"]=ps.PageCount;
首页：ViewState["page"]=0;DataSource=ps;DataBind();
下一页：ViewState["page"]=int.Parse(ViewState["page"].ToString())-1;DataSource=ps;DataBind();
上一页：ViewState["page"]=int.Parse(ViewState["page"].ToString())+1;DataSource=ps;DataBind();
尾页： ViewState["page"] = int.Parse(ViewState["count"].ToString()) - 1;DataSource=ps;DataBind();
 LabSum.Text = ps.DataSourceCount.ToString ();//总数据条数

//输出提示信息
 Page.ClientScript.RegisterStartupScript(Page.GetType(), "message", "<script language='javascript' defer>alert('对不起！您还没登录，请先登录！');window.location='Default.aspx'</script>");
//获得时间
    <script type="text/javascript"> 
    function showTime() 
    { 
        var now = new Date();   
        var month=now.getMonth()+1;     
        document.getElementById("labTime").innerHTML ="今天是：" +now.getFullYear ()+"-"+month+"-"+now.getDate () +"     " +now.getHours() + ":" + now.getMinutes() + ":" + now.getSeconds(); 
        window.setTimeout("showTime()",1000); 
        
    }     
    </script>

//DataList
 RepeatDirection="Horizontal" 数据横向显示 Vertical数据竖向显示 RepeatColumns="2"

//OnItemCommand
CommandArgument='<%# DataBinder.Eval(Container.DataItem, "商品编号") %>' 
CommandName="buy"
protected void dLRecommend_ItemCommand(object source, DataListCommandEventArgs e)
    {
        if (e.CommandName == "detailSee")
        {
            AddressBack(e);
        }
        else if (e.CommandName == "buy")
        {
            AddShopCart(e);
        }

    }

//查找控件
Textbox t e.Item.FindControl("id") as Textbox 

//DataView的RowFilter属性实现SQL语句SELECT语句所实现的功能
DataTable不是数据库中的数据或修改了未保存
Session["table"]=dt;
DataTable dt1=(DataTable)Session["table"];
DataView dv=new DataView(dt1);
dv.RowFilter="商品名称 like '%"+TextBox1.Text.Trim()+"%'";
DataSource=dv;
DataBind();

//删除前确认
OnClientClick= "return confirm('您确定要删除这个附件吗？')"

//绑定DrorList
第一种: 　　　　　　　　　  
  DataSet   ds=   new   DataSet();       
  ds   =   cls2.SelectOle();   
 DdlSearch1.Items.Clear();
  DropDownList1.DataSource   =   ds.Tables["My"].DefaultView;           
  DropDownList1.DataTextField   =   "dep_Name";       
  DropDownList1.DataValueField   =   "dep_Id";       
  DropDownList1.DataBind();  
  第二种：
  DataSet   set1=   new   DataSet();     
  set1   =   cls2.SelectOle();   
 DdlSearch1.Items.Clear();
  for   (int   num1   =   0;   num1   <   set1.Tables["My"].Rows.Count;   num1++)   
  {   
  DropDownList1.Items.Add(set1.Tables["My"].Rows[num1][1].ToString());   
  }  

//DrowList插入空项
DropDownList1.Items.Insert(0, new ListItem("", ""));//插入空项，此举必须放到数据绑定之后 

//记录滚动条位置
MaintainScrollPositionOnPostback="true"

//连接到邮箱
<a href="mailto:[e-mail]">

//文本缩进
text-indent: 2em

//绑定图片
<img src='<%#Eval("ProductUrl","Ftp/{0}")%>' width="135px" height="100px;" border="0" title ='<%#Eval ("ProductName") %>'>

//前台按钮值传到后台
<asp:ImageButton ID="imagebtnRefine" runat="server" CommandName="buy" CommandArgument='<%# DataBinder.Eval(Container.DataItem, "商品编号") %>' ImageUrl="~/images/购买.jpg"  />

//手动创建DataTable
dtTable = new DataTable();
DataColumn column1 = new DataColumn("序号");
dtTable.Columns.Add(column1);
DataRow row;
row = dtTable.NewRow();
row["序号"] = key.ToString();
dtTable.Rows.Add(row);

//手动为数据控件中的控件添加事件
<asp:TextBox ID="txtNum" runat="server" Text =<%#Eval("Num") %> Width =60px  OnTextChanged="txtNum_TextChanged"></asp:TextBox>

protected void txtNum_TextChanged(object sender, EventArgs e)
    {
        hashCar = (Hashtable)Session["ShopCart"];  //获取其购物车
        foreach (GridViewRow gvr in this.gvShopCart.Rows)
        {

            TextBox otb = (TextBox)gvr.FindControl("txtNum"); //找到用来输入数量的TextBox控件 
            int count = Int32.Parse(otb.Text);//获得用户输入的数量值
            string BookID = gvr.Cells[1].Text;//得到该商品的ID代
            hashCar[BookID] = count;//更新hashTable表

        }
        Session["ShopCart"] = hashCar;//更新购物车
        bind();
}