ListView控件(一)--增，删，改，查

在解决获到ListView Insert 获取输入值的处理办法可参考以下：

http://www.cnblogs.com/chencaixia/articles/989498.html

ASP.NET3.5中包含了新的数据绑定控件--ListView，这是一个类似与repeater与gridview结合的控件，可以实现添加，删除功能，同时还可以像repeater一样灵活的控制页面的布局。该控件包含了很多新的模板，比如GroupTemplate等新增的模板，可以方便的分组显示数据。详细的大家可以去查MSDN文档。
我一直认为学习数据绑定控件从最简单的增删改查开始，可以对该控件有较深刻的理解，这样可以举一反三，在进行综合运用。今天这篇文章还是从最基本的数据操作开始，对ListView有个感性的认识。
首先看一下程序运行的效果：



页面源码：


<asp:ListView ID="ListView1" runat="server" OnSelectedIndexChanging="ListView1_SelectedIndexChanging"


OnItemCommand="ListView1_ItemCommand"


OnItemEditing="ListView1_ItemEditing" OnItemCanceling="ListView1_ItemCanceling"


OnItemDataBound="ListView1_ItemDataBound" OnPagePropertiesChanging="ListView1_PagePropertiesChanging"


OnItemInserting="ListView1_ItemInserting" OnItemUpdating="ListView1_ItemUpdating"


OnSorting="ListView1_Sorting" EnableViewState="true"


InsertItemPosition="LastItem" onitemdeleting="ListView1_ItemDeleting">


<LayoutTemplate>


<asp:PlaceHolder ID="itemPlaceholder" runat="server"></asp:PlaceHolder>


<p>


<asp:DataPager ID="MyPage" runat="server" PageSize="6">


<Fields>


<asp:NumericPagerField ButtonCount="10" PreviousPageText="<-- " NextPageText="-->" />


<%-- <asp:NextPreviousPagerField ButtonType="Button" ShowFirstPageButton="true" ShowLastPageButton="true"


ShowNextPageButton="true" ShowPreviousPageButton="true" />--%>


</Fields>


</asp:DataPager>


</p>


</LayoutTemplate>


<ItemTemplate>


<i>


<%#Eval("SupplierID")%></i>


<p>


<b>


<%#Eval("CompanyName")%></b></p>


<p>


<%#Eval("ContactName")%></p>


<p>


<%#Eval("Address")%></p>


<p>


<%#Eval("City")%></p>


<asp:Button ID="btnEdit" runat="server" Text="Edit" CommandName="Edit" />


<asp:Button ID="btnDelete" runat="server" Text="Delete" CommandName="Delete" />


<%-- <asp:LinkButton ID="lbtnSort" runat="server" Text="Sort" CommandName="Sort" CommandArgument="CompanyName" ></asp:LinkButton>--%>


</ItemTemplate>


<EditItemTemplate>


<asp:TextBox ID="txtMy" runat="server" Text='<%#bind("SupplierID") %>'></asp:TextBox>


<asp:TextBox ID="TextBox1" runat="server" Text='<%#bind("CompanyName") %>'></asp:TextBox>


<asp:TextBox ID="TextBox2" runat="server" Text='<%#bind("ContactName") %>'></asp:TextBox>


<asp:TextBox ID="TextBox3" runat="server" Text='<%#bind("Address") %>'></asp:TextBox>


<asp:TextBox ID="TextBox4" runat="server" Text='<%#bind("City") %>'></asp:TextBox>


<asp:Button ID="btnUpdate" runat="server" Text="Update" CommandName="Update" />


<asp:Button ID="btnCancle" runat="server" Text="Cancle" CommandName="Cancel" />


</EditItemTemplate>


<InsertItemTemplate>


<asp:TextBox ID="txtMy" runat="server" Text='<%#bind("SupplierID") %>'></asp:TextBox>


<asp:TextBox ID="TextBox1" runat="server" Text='<%#bind("CompanyName") %>'></asp:TextBox>


<asp:TextBox ID="TextBox2" runat="server" Text='<%#bind("ContactName") %>'></asp:TextBox>


<asp:TextBox ID="TextBox3" runat="server" Text='<%#bind("Address") %>'></asp:TextBox>


<asp:TextBox ID="TextBox4" runat="server" Text='<%#bind("City") %>'></asp:TextBox>


<asp:Button ID="btnUpdate" runat="server" Text="Insert" CommandName="Insert" />


<asp:Button ID="btnCancle" runat="server" Text="Cancle" CommandName="Cancel" />


</InsertItemTemplate>


<ItemSeparatorTemplate>


<div style="height: 0px; border-top: dashed 1px #ff0000">


</div>


</ItemSeparatorTemplate>




</asp:ListView>

这部分代码中有个重要的部分就是通过<LayoutTemplate>模板来设置控件的样式，布局，这也是新增的模板。在VS.NET2008的正式版本中，要正常运行页面必须在该模板中加入一个名为itemPlaceholder的PlaceHolder控件。要不会出现如下异常：
An item placeholder must be specified on ListView 'ListView1'. Specify an item placeholder by setting a control's ID property to "itemPlaceholder".
<ItemTemplate>模板用来绑定显示到页面上的数据， <EditItemTemplate>用来显示处于编辑状态的时候显示的数据，其他的可以以此类推。
与ListView还搭配的一起使用了新增的DataPager控件，这个主要是用于ListView控件的分页，是新增的分页空也，可以方便，高效的进行分页。
后台代码：


string ConStr = ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ConnectionString;


protected void Page_Load(object sender, EventArgs e)


{


if (!IsPostBack)


{


ViewState["SupplierID"] = "SupplierID";


ViewState["Direction"] = "DESC";


BindListView();


}




}




private void BindListView()


{


string QueryCon = "SELECT SupplierID,CompanyName,ContactName,Address,City FROM Suppliers";


SqlConnection NorthWindCon = new SqlConnection(ConStr);


SqlDataAdapter NorthWindDa = new SqlDataAdapter(QueryCon, ConStr);


DataSet Ds = new DataSet();


NorthWindDa.Fill(Ds, "Suppliers");


ListView1.DataKeyNames = new string[] { "SupplierID" };


DataView Dv = Ds.Tables["Suppliers"].DefaultView;


//排序表达式


string SortExpress = (string)ViewState["SupplierID"] + " " + (string)ViewState["Direction"];


Dv.Sort = SortExpress;


//绑定数据源


//ListView1.DataSource = Ds.Tables["Suppliers"];


ListView1.DataSource = Dv;


ListView1.DataBind();




}






protected void ListView1_ItemEditing(object sender, ListViewEditEventArgs e)


{


ListView1.EditIndex = e.NewEditIndex;


BindListView();


}






protected void ListView1_ItemDataBound(object sender, ListViewItemEventArgs e)


{


if (e.Item.ItemType == ListViewItemType.DataItem)


{


((Button)e.Item.FindControl("btnDelete")).Attributes["onclick"] = "if(!confirm('你真的要删除这条记录么?'))return false;";


}




}




protected void ListView1_ItemCanceling(object sender, ListViewCancelEventArgs e)


{


//取消编辑


if (e.CancelMode == ListViewCancelMode.CancelingEdit)


{


//e.Cancel = true;


ListView1.EditIndex = -1;


BindListView();


ShowMessage("取消编辑");


}


else if (e.CancelMode == ListViewCancelMode.CancelingInsert)


{


//BindListView();


return;


}






}






protected void ListView1_ItemInserting(object sender, ListViewInsertEventArgs e)


{


((TextBox)ListView1.InsertItem.FindControl("txtMy")).ReadOnly = true;


string CompanyName = Server.HtmlEncode(((TextBox)ListView1.InsertItem.FindControl("TextBox1")).Text.ToString());


string ContactName = Server.HtmlEncode(((TextBox)ListView1.InsertItem.FindControl("TextBox2")).Text.ToString());


string Address = Server.HtmlEncode(((TextBox)ListView1.InsertItem.FindControl("TextBox3")).Text.ToString());


string City = Server.HtmlEncode(((TextBox)ListView1.InsertItem.FindControl("TextBox4")).Text.ToString());




string InsertQuery = "INSERT INTO Suppliers (CompanyName,ContactName,Address,City) VALUES ('" + CompanyName + "','" + ContactName + "','" + Address + "','" + City + "')";


SqlConnection InsertCon = new SqlConnection(ConStr);


SqlCommand InsertCmd = new SqlCommand(InsertQuery, InsertCon);


try


{


InsertCon.Open();


InsertCmd.ExecuteNonQuery();


BindListView();


//将插入行显示到最后


ListView1.InsertItemPosition = InsertItemPosition.LastItem;




}


catch


{


ShowMessage("插入新数据出错，请重新输入");


}


finally


{


InsertCon.Dispose();


InsertCmd.Dispose();


}


}




protected void ListView1_ItemUpdating(object sender, ListViewUpdateEventArgs e)


{


string KeyId = ListView1.DataKeys[e.ItemIndex].Value.ToString();


//找到listview改行的数据集合


string CompanyName = Server.HtmlEncode(((TextBox)ListView1.Items[e.ItemIndex].FindControl("TextBox1")).Text.ToString());


string ContactName = Server.HtmlEncode(((TextBox)ListView1.Items[e.ItemIndex].FindControl("TextBox2")).Text.ToString());


string Address = Server.HtmlEncode(((TextBox)ListView1.Items[e.ItemIndex].FindControl("TextBox3")).Text.ToString());


string City = Server.HtmlEncode(((TextBox)ListView1.Items[e.ItemIndex].FindControl("TextBox4")).Text.ToString());


string UpdateStr = "UPDATE Suppliers SET CompanyName='" + CompanyName + "',ContactName='" + ContactName + "'," +


"Address='" + Address + "',City='" + City + " 'WHERE SupplierID='" + KeyId + "' ";


SqlConnection UpdateCon = new SqlConnection(ConStr);


SqlCommand UpdateCmd = new SqlCommand(UpdateStr, UpdateCon);


try


{


UpdateCon.Open();


UpdateCmd.ExecuteNonQuery();


ListView1.EditIndex = -1;


BindListView();


}


catch


{


ShowMessage("更新出错，请重新编辑");


}


finally


{


UpdateCon.Dispose();


UpdateCmd.Dispose();


}


}






protected void ListView1_Sorting(object sender, ListViewSortEventArgs e)


{


if (ViewState["SupplierID"].ToString() == e.SortExpression)


{


if (ViewState["Direction"].ToString() == "DESC")


{


ViewState["Direction"] = "ASC";


}


else


{


ViewState["Direction"] = "DESC";


}


}


else


{


ViewState["SupplierID"] = e.SortExpression;


}


BindListView();


}






private void ShowMessage(string Message)


{


Literal TxtMsg = new Literal();


TxtMsg.Text = "<script>alert('" + Message + "')</script>";


Page.Controls.Add(TxtMsg);


}




protected void ListView1_ItemDeleting(object sender, ListViewDeleteEventArgs e)


{


string KeyID = ListView1.DataKeys[e.ItemIndex].Value.ToString();


string DeleteStr = "DELETE FROM Suppliers WHERE SupplierID='" + KeyID + "'";


SqlConnection DeleteCon = new SqlConnection(ConStr);


SqlCommand DeleteCmd = new SqlCommand(DeleteStr, DeleteCon);


try


{


DeleteCon.Open();


DeleteCmd.ExecuteNonQuery();


BindListView();


ShowMessage("删除成功");


}


catch


{


ShowMessage("删除出错，请检查数据是否有关联");


}


finally


{


DeleteCon.Dispose();


DeleteCmd.Dispose();


}


}

以前的edit_cancel事件在ListView控件中为item_cancel，在该事件中可以判断是取消编辑还是取消插入新的数据。大家可以看代码。本篇文章主要是对ListView控件一些基本的事件的运用。下一篇会继续深入的学习该控件。