【ASP.NET2.0学习笔记】开发投票系统

//文章作者：叶茂（猫猫）（本学习笔记系列文章拒绝任何形式的修改、加工或转载）




这个投票系统的大部分源码来自马军主编的《精通ASP.NET 2.0 网络应用系统开发》，但是按照原文提供的代码，系统是无法在VS2005下编译通过的。鉴于此，猫重写了部分代码使其能正常运行于VS2005，现贴出来给大家分享。

1、系统功能设计

投票选项管理

对选项投票

投票情况查看

2、数据库设计

VoteDB



3、存储过程设计

添加投票选项

CREATE PROCEDURE Proc_AddVote

@Item varchar(100)

AS

INSERT INTO

Votes(Item,VoteCount)

VALUES(@Item,0)

RETURN @@Identity

GO

删除投票选项

CREATE PROCEDURE Proc_DeleteVote

@VoteID int

AS

DELETE Votes

WHERE VoteID = @VoteID

GO

更新投票选项

CREATE PROCEDURE Proc_UpdateVote

@VoteID int

AS

UPDATE Votes

SET VoteCount = VoteCount + 1

WHERE VoteID = @VoteID

GO

显示所有投票项目

CREATE PROCEDURE Pr_GetVotes

AS

SELECT *

FROM Votes

Order By VoteID

GO

4、数据库访问层设计

在App_Code文件夹下添加一个.cs类文件用来封装对以上存储过程的调用方法。

using System;

using System.Data;

using System.Configuration;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using SQLHelper;

using System.Data.SqlClient;

namespace WebVote

{

/// <summary>

/// Summary description for Vote

/// </summary>

public class Vote

{

public SqlDataReader GetVotes()

{

///定义类SQLHelper

SQLHelper.SQLHelper sqlHelper = new SQLHelper.SQLHelper();

///定义保存从数据库获取的结果的DataReader

SqlDataReader dr = null;

try

{

///执行存储过程

sqlHelper.RunProc("Proc_GetVotes", out dr);

}

catch (Exception ex)

{

///抛出执行数据库异常

SystemError.CreateErrorLog(ex.Message);

throw new Exception(ex.Message, ex);

}

///返回从数据库获取的结果

return (dr);

}

public int AddVote(String sItem)

{

///定义类SQLHelper

SQLHelper.SQLHelper sqlHelper = new SQLHelper.SQLHelper();

///创建访问数据库的参数

SqlParameter[] paramList = {

sqlHelper.CreateInParam("@Item", SqlDbType.VarChar,100,sItem)

};

try

{

///执行存储过程

return (sqlHelper.RunProc("Proc_AddVote", paramList));

}

catch (Exception ex)

{

///抛出执行数据库异常

SystemError.CreateErrorLog(ex.Message);

throw new Exception(ex.Message, ex);

}

}

public void UpdateVote(int nVoteID)

{

///定义类SQLHelper

SQLHelper.SQLHelper sqlHelper = new SQLHelper.SQLHelper();

///创建访问数据库的参数

SqlParameter[] paramList = {

sqlHelper.CreateInParam("@VoteID", SqlDbType.Int, 4,nVoteID)

};

try

{

///执行存储过程

sqlHelper.RunProc("Proc_UpdateVote", paramList);

}

catch (Exception ex)

{

///抛出执行数据库异常

SystemError.CreateErrorLog(ex.Message);

throw new Exception(ex.Message, ex);

}

}

public void DeleteVote(int nVoteID)

{

///定义类SQLHelper

SQLHelper.SQLHelper sqlHelper = new SQLHelper.SQLHelper();

///创建访问数据库的参数

SqlParameter[] paramList = {

sqlHelper.CreateInParam("@VoteID", SqlDbType.Int, 4,nVoteID)

};

try

{

///执行存储过程

sqlHelper.RunProc("Proc_DeleteVote", paramList);

}

catch (Exception ex)

{

///抛出执行数据库异常

SystemError.CreateErrorLog(ex.Message);

throw new Exception(ex.Message, ex);

}

}

}

}

对于数据访问层，需要使用一个SQLHelper的DLL文件（下载地址：http://d.download.csdn.net/down/661742/zhaobisha 将其粘贴到Bin文件夹中。

5、程序页面设计

主页面（Default.aspx）

...

<form id="form1" runat="server">

<div>

<asp:LinkButton ID="ItemManageLink" runat="server" BackColor="Black" ForeColor="White"

Height="24px" Width="149px" PostBackUrl="VoteItemManage.aspx">投票选项管理</asp:LinkButton><br />

<br />

<asp:LinkButton ID="OnlineVoteLink" runat="server" BackColor="Black" ForeColor="White"

Height="24px" Width="149px" PostBackUrl="~/OnlineVote.aspx">在线投票</asp:LinkButton> <br />

<br />

<asp:LinkButton ID="ViewVoteLink" runat="server" BackColor="Black" ForeColor="White"

Height="24px" Width="149px" PostBackUrl="~/ShowVoteResult.aspx">查看投票结果</asp:LinkButton></div>

</form>

...

投票选项管理页面（VoteItemManage.aspx）



...

<form id="form1" runat="server">

<div>

<asp:ListBox ID="ItemList" runat="server" Rows="10" Width="150px"></asp:ListBox>

<asp:Button ID="deleteBtn" runat="server" CommandName="delete" OnClientClick="deleteBtn_Click"

Text="删除此项" OnClick="deleteBtn_Click" /> <br />

<asp:TextBox ID="Item" runat="server" Height="18px" Width="290px"></asp:TextBox>

<asp:Button ID="AddBtn" runat="server" Text="增加新选项" OnClick="AddBtn_Click" /></div>

</form>

...

在线投票页面（OnlineVote.aspx）



...

<form id="form1" runat="server">

<div>

<asp:GridView ID="VoteList" runat="server" AutoGenerateColumns="False" BackColor="White" BorderColor="#CC9966" BorderStyle="None" BorderWidth="1px" CellPadding="4" DataKeyNames="VoteID">

<Columns>

<asp:TemplateField HeaderText="勾选" SortExpression="VoteID">

<ItemTemplate>

<asp:CheckBox ID="VoteCheck" runat="server" />

</ItemTemplate>

<ItemStyle HorizontalAlign="Center" />

</asp:TemplateField>

<asp:BoundField DataField="Item" HeaderText="投票选项" SortExpression="Item" >

<ControlStyle BackColor="#E0E0E0" />

<ItemStyle Width="200px" HorizontalAlign="Center" />

</asp:BoundField>

<asp:BoundField DataField="VoteID" ShowHeader="False" SortExpression="VoteID" Visible="False" />

</Columns>

<FooterStyle BackColor="#FFFFCC" ForeColor="#330099" />

<PagerStyle BackColor="#FFFFCC" ForeColor="#330099" HorizontalAlign="Center" />

<HeaderStyle BackColor="#990000" Font-Bold="True" ForeColor="#FFFFCC" />

<RowStyle BackColor="White" ForeColor="#330099" />

<SelectedRowStyle BackColor="#FFCC66" Font-Bold="True" ForeColor="#663399" />

</asp:GridView>

</div>

<asp:Button ID="VoteBtn" runat="server" Text="我要投票" OnClick="VoteBtn_Click" />

<asp:Button ID="ShowVote" runat="server" Text="查看结果" PostBackUrl="~/ShowVoteResult.aspx" />

<asp:Label ID="VoteMessage" runat="server">投票成功!</asp:Label><br />

<br />

</form>

...

查看投票结果页面（ShowVoteResult.aspx）



...

<form id="form1" runat="server">

<div>

<asp:GridView ID="VoteList" runat="server" BackColor="White" BorderColor="#CC9966"

BorderStyle="None" BorderWidth="1px" CellPadding="4" AutoGenerateColumns="False">

<FooterStyle BackColor="#FFFFCC" ForeColor="#330099" />

<RowStyle BackColor="White" ForeColor="#330099" />

<SelectedRowStyle BackColor="#FFCC66" Font-Bold="True" ForeColor="#663399" />

<PagerStyle BackColor="#FFFFCC" ForeColor="#330099" HorizontalAlign="Center" />

<HeaderStyle BackColor="#990000" Font-Bold="True" ForeColor="#FFFFCC" />

<Columns>

<asp:BoundField DataField="Item" HeaderText="投票项目" SortExpression="Item" />

<asp:TemplateField HeaderText="所占总票的百分比">

<ItemStyle Width="300px" />

<ItemTemplate>

<asp:Image ID="VoteDegree" runat="server" Width="" Height="20px" ImageUrl="~/Images/Vote.gif" />

</ItemTemplate>

</asp:TemplateField>

<asp:BoundField DataField="VoteCount" HeaderText="票数" SortExpression="VoteCount" />

</Columns>

</asp:GridView>

<asp:Label ID="VoteMessage" runat="server" Text="Label"></asp:Label> <asp:Button

ID="Button1" runat="server" PostBackUrl="~/OnlineVote.aspx" Text="返回继续投票" /><br />

</div>

</form>

...

6、页面功能设计

投票选项管理（VoteItemManage.aspx.cs）

...

protected void Page_Load(object sender, EventArgs e)

{

if (!Page.IsPostBack)

{

BindVoteListData();

}

}

protected void BindVoteListData()

{

WebVote.Vote vote = new Vote();

SqlDataReader rs = vote.GetVotes();

ItemList.DataTextField = "Item";

ItemList.DataValueField = "VoteID";

ItemList.DataSource = rs;

ItemList.DataBind();

rs.Close();

}

protected void AddBtn_Click(object sender, EventArgs e)

{

if (Item.Text.Length > 0)

{

WebVote.Vote vote = new Vote();

try

{

vote.AddVote(Item.Text.Trim());

BindVoteListData();

Response.Write("<script>alert('" + ASPNET2System.OPERATIONADDSUCCESSMESSAGE + "')</script>");

}

catch (Exception ex)

{

Response.Redirect("~/DesktopModules/ErrorPage.aspx?ErrorUrl=" + ASPNET2System.RedirectErrorUrl(Request.RawUrl) + "&ErrorMessage=" + ex.Message.Replace("/n", ""));

}

}

}

protected void deleteBtn_Click(object sender, EventArgs e)

{

if (ItemList.SelectedIndex <= -1)

{

Response.Write("<script>alert('" + ASPNET2System.OPERATIONNOSELECTMESSAGE + "')</script>");

return;

}

WebVote.Vote vote = new Vote();

try

{

vote.DeleteVote(int.Parse(ItemList.SelectedValue));

BindVoteListData();

}

catch (Exception ex)

{

Response.Redirect("~/DesktopModules/ErrorPage.aspx?ErrorUrl=" + ASPNET2System.RedirectErrorUrl(Request.RawUrl) + "&ErrorMessage=" + ex.Message.Replace("/n", ""));

}

}

...

在线投票（OnlineVote.aspx.cs）

...

protected void Page_Load(object sender, EventArgs e)

{

if (!Page.IsPostBack)

{

BindVoteListData();

VoteMessage.Visible = false;

}

}

private void BindVoteListData()

{

WebVote.Vote vote = new Vote();

SqlDataReader rs = vote.GetVotes();

VoteList.DataSource = rs;

VoteList.DataBind();

rs.Close();

}

protected void VoteBtn_Click(object sender, EventArgs e)

{

WebVote.Vote vote = new Vote();

try

{

//for (int i = 0; i <= VoteList.Rows.Count - 1; i++)

foreach (GridViewRow row in VoteList.Rows)

{

CheckBox chk = (CheckBox)row.FindControl("VoteCheck");

if (chk != null)

{

if (chk.Checked == true)

{

vote.UpdateVote(int.Parse(VoteList.DataKeys[row.RowIndex].Value.ToString()));

VoteMessage.Visible = true;

}

}

}

Response.Write("<script>window.alert('感谢投票!')</script>");

}

catch (Exception ex)

{

Response.Redirect("~/DesktopModules/ErrorPage.aspx?ErrorUrl=" + ASPNET2System.RedirectErrorUrl(Request.RawUrl) + "&ErrorMessage=" + ex.Message.Replace("/n", ""));

}

}

...

查看投票结果（ShowVoteResult.aspx.cs）

...

int voteTotal = 0;

protected void Page_Load(object sender, EventArgs e)

{

SetVoteTotal();

if (!Page.IsPostBack)

{

BindVoteListData();

ShowImageDegree();

VoteMessage.Text = "总票数：" + voteTotal.ToString() + "票";

}

}

protected void BindVoteListData()

{

WebVote.Vote vote = new Vote();

SqlDataReader rs = vote.GetVotes();

VoteList.DataSource = rs;

VoteList.DataBind();

rs.Close();

}

protected void SetVoteTotal()

{

WebVote.Vote vote = new Vote();

SqlDataReader rs = vote.GetVotes();

voteTotal = 0;

while (rs.Read())

{

voteTotal += int.Parse(rs["voteCount"].ToString());

}

rs.Close();

}

protected void ShowImageDegree()

{

foreach (GridViewRow row in VoteList.Rows)

{

Image img = (Image)row.FindControl("VoteDegree");

if (img != null)

{

//vote.UpdateVote(Int32.Parse(VoteList.DataKeys[row.RowIndex].Value.ToString()));

string dw = VoteList.Rows[row.RowIndex].Cells[2].Text.ToString();

img.Width = FormatVoteImage(FormatVoteCount(dw));

}

}

}

public int FormatVoteCount(string voteCount)

{

if (voteCount.Length <= 0)

{

return (0);

}

if (voteTotal > 0)

{

return (int.Parse(voteCount) * 100 / voteTotal);

}

return (0);

}

public int FormatVoteImage(int voteCount)

{

return (voteCount * 3);

}

...

7、小结

SQLHelper以及Gridview控件的使用为本系统实现的主要手段。其中，Gridview控件中的遍历数据格的代码是最基础也是最需要掌握的内容。