Sử dụng ZedGraph để tạo biểu đồ kiểu Horizontal Bars trong Asp.net

By Unknown - Saturday, June 13, 2015 - No Comments

(Tạo biểu đồ kiểu Horizontal Bars lấy dữ liệu từ SQL Server) – Bài viết trước thủ thuật lập trình đã hướng dẫn các bạn cách tạo biểu đồ kiểu Pie lấy dữ liệu từ SQL. Hôm nay thủ thuật tin học sẽ giới thiệu 1 cách tạo biểu đồ khác, đó là biểu đồ kiểu cột nằm ngang (Horizontal Bars). Với biểu đồ hình cột người sử dụng dễ dàng hơn trong việc so sánh và đánh giá giữa các tiêu chí với nhau.

Nghe những bài hát đỉnh nhất về Thấy cô giáo - Nghe trên Youtube

- B1: Download CSDL Northwind

- B2: Bổ xung thêm 2 store:
+ Pro_Categories_List: Liệt kê toàn bộ danh sách Category
+ Pro_ProductByCategory: Đếm số sản phẩm theo từng Category

CREATE PROCEDURE [dbo].[Pro_Categories_List]

@Keyword nvarchar(250)

declare @strSQL nvarchar(1000)

declare @strWhere nvarchar(500)

declare @strOrder nvarchar (50)

set @strSQL= 'SELECT CategoryID,CategoryName from Categories'

set @strWhere =' Where 1=1 '

if @Keyword<>''

set @strWhere= @strWhere +' And (CategoryName like N''%' +@Keyword+'%'' )'

set @strOrder =' Order by CategoryName'

set @strSQL=@strSQL+@strWhere+@strOrder

print @strSQL

exec sp_executesql @strSQL

CREATE PROCEDURE [dbo].[Pro_ProductByCategory]

declare @strSQL nvarchar(1000)

declare @strWhere nvarchar(500)

declare @strOrder nvarchar (50)

set @strSQL= 'SELECT Products.CategoryID, Categories.CategoryName,COUNT(Products.ProductID) AS TotalNumber

FROM Products INNER JOIN

Categories ON Products.CategoryID = Categories.CategoryID

GROUP BY Products.CategoryID, Categories.CategoryName

ORDER BY dbo.Categories.CategoryName'

set @strSQL=@strSQL

print @strSQL

exec sp_executesql @strSQL

- B3: Tạo Project trong Microsoft Visual Studio 2010

Trong Visual Studio tạo 1 Class có tên: Utility và nhập đoạn Code phía dưới cho Class này.

Imports System.Data.SqlClient

Imports System.Data

Namespace ZedGraphHorizontalBarsCharts

Public Class SqlDataProvider

#Region "Membres Prives"

Shared _IsError As Boolean = False

Private _connectionString As String

#End Region

#Region "Constructeurs"

Public Sub New()

Try

_connectionString = ConfigurationManager.ConnectionStrings("SiteSqlServer").ConnectionString

_IsError = False

Catch ex As Exception

_IsError = True

End Try

End Sub

#End Region

#Region "Proprietes"

Public ReadOnly Property ConnectionString() As String

Get

Return _connectionString

End Get

End Property

#End Region

#Region "Functions"

Public Function FillTable(ByVal sql As String) As DataTable

Try

Dim tb As New DataTable

Dim adap As New SqlDataAdapter(sql, _connectionString)

adap.Fill(tb)

Return tb

Catch ex As Exception

Return Nothing

End Try

End Function

Public Function FillTable(ByVal ProcName As String, ByVal ParamArray Para() As ObjectPara) As DataTable

Try

Dim tb As New DataTable

Dim adap As New SqlDataAdapter(ProcName, _connectionString)

adap.SelectCommand.CommandType = CommandType.StoredProcedure

If Not Para Is Nothing Then

For Each p As ObjectPara In Para

adap.SelectCommand.Parameters.Add(New SqlParameter(p.Name, p.Value))

End If

adap.Fill(tb)

Return tb

Catch ex As Exception

Return Nothing

End Try

End Function

#End Region

End Class

Public Class ObjectPara

Dim _name As String

Dim _Value As Object

Sub New(ByVal Pname As String, ByVal PValue As Object)

_name = Pname

_Value = PValue

End Sub

Public Property Name() As String

Get

Return _name

End Get

Set(ByVal value As String)

_name = value

End Set

End Property

Public Property Value() As Object

Get

Return _Value

End Get

Set(ByVal value As Object)

_Value = value

End Set

End Property

End Class

End Namespace

Chú ý: Thuộc tính SiteSqlServer chính là chuỗi Connect với SQL Server trong file Web.Config

- B4: Download thư viện ZedGraph tại địa chỉ:
http://sourceforge.net/projects/zedgraph/files/zedgraph%20dll%20only/

- B5: Giải nén ZedGraph, và References ZedGraph.Web vào Project vừa tạo.

- B6: Mở file Default.aspxdưới dạng HTML và nhập mã HTML

<%@ Page Title="ZedGraph Horizontal Bars Charts in ASP.Net" Language="vb" MasterPageFile="~/Site.Master" AutoEventWireup="false" CodeBehind="Default.aspx.vb" Inherits="ZedGraphHorizontalBarsCharts._Default" %>

<%@ Register assembly="ZedGraph.Web" namespace="ZedGraph.Web" tagprefix="cc1" %>

<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">

<h1>

ZedGraph Horizontal Bars Charts in ASP.Net

</h1>

<br />

<cc1:ZedGraphWeb ID="ZedGraphWeb1" width="600" Height="475" runat="server">

</cc1:ZedGraphWeb>

</asp:Content>

- B7: Viết Code cho file Default.aspx

C# Code

//Visit http://www.laptrinhdotnet.com for more ASP.NET Tutorials

using Microsoft.VisualBasic;

using System;

using System.Collections;

using System.Collections.Generic;

using System.Data;

using System.Diagnostics;

using ZedGraph;

using ZedGraph.Web;

using System.Drawing;

namespace ZedGraphHorizontalBarsCharts

{

public partial class _Default : System.Web.UI.Page

{

#region "Private Members"

private string[] Labels;

private double[] XAxis;

#endregion

#region "Bind Data"

private DataTable BindCategories()

{

SqlDataProvider objSQL = new SqlDataProvider();

DataTable objBind = objSQL.FillTable("Pro_Categories_List", new ObjectPara("@Keyword", ""));

return objBind;

}

private DataTable BindProduct()

{

SqlDataProvider objSQL = new SqlDataProvider();

DataTable objBind = objSQL.FillTable("Pro_ProductByCategory");

return objBind;

}

#endregion

#region "Event Handles"

protected void ucZedGraph_RenderGraph1(ZedGraph.Web.ZedGraphWeb z, System.Drawing.Graphics g, ZedGraph.MasterPane masterPane)

{

GraphPane myPane = masterPane[0];

BarItem myCurve = default(BarItem);

DataTable objBind = new DataTable();

string ObjectName = "";

DataRow dRow = null;

int i = 0;

objBind = BindCategories();

if (objBind != null)

{

if (objBind.Rows.Count > 0)

{

Labels = new string[objBind.Rows.Count];

XAxis = new double[objBind.Rows.Count];

for (i = 0; i <= objBind.Rows.Count-1; i++)

{

dRow = objBind.Rows[i];

ObjectName = dRow["CategoryName"].ToString();

if (!string.IsNullOrEmpty(ObjectName))

{

Labels[i] = ObjectName;

}

if (Labels != null)

{

objBind = BindProduct();

i = 0;

if (objBind.Rows.Count > 0)

{

foreach (DataRow row in objBind.Rows)

{

if (row != null)

{

XAxis[i] =Convert.ToDouble(row["TotalNumber"]);

i = i + 1;

}

//Set the title Chart

myPane.Title.Text = "Horizontal Bars Charts";

myPane.Title.FontSpec.FontColor = Color.Blue;

myPane.Title.FontSpec.Size = 14f;

//Set the title and axis labels

//axis X

myPane.XAxis.Title.Text = "Number";

myPane.XAxis.Title.FontSpec.Size = 12f;

//axis Y

myPane.YAxis.Title.Text = "Category";

myPane.YAxis.Title.FontSpec.Size = 12f;

//axis X

myCurve = myPane.AddBar("", XAxis, null, Color.Blue);

// Fill the bar with a Blue-white-Blue color gradient for a 3d look

myCurve.Bar.Fill = new Fill(Color.Green, Color.White, Color.Green, 90f);

//axis X

myPane.YAxis.Scale.TextLabels = Labels;

myPane.YAxis.Scale.AlignH = AlignH.Right;

// Set the XAxis to Text type

myPane.YAxis.Type = AxisType.Text;

// Make the bars Vertical by setting the BarBase to "X"

myPane.BarSettings.Type = BarType.Cluster;

myPane.BarSettings.Base = BarBase.Y;

//Set Font Value for Axis

myPane.YAxis.Scale.FontSpec.Size = 8f;

myPane.XAxis.Scale.FontSpec.Size = 8f;

// Fill the axis background with a color gradient

myPane.Chart.Fill = new Fill(Color.White, Color.FromArgb(255, 255, 166), 45f);

masterPane.AxisChange(g);

}

#endregion

}

VB.NET Code

Imports ZedGraph

Imports ZedGraph.Web

Imports System.Drawing

Namespace ZedGraphHorizontalBarsCharts

Public Class _Default

Inherits System.Web.UI.Page

#Region "Private Members"

Private Labels As String()

Private XAxis As Double()

#End Region

#Region "Bind Data"

Private Function BindCategories() As DataTable

Dim objSQL As New SqlDataProvider

Dim objBind As DataTable = objSQL.FillTable("Pro_Categories_List", New ObjectPara("@Keyword", ""))

Return objBind

End Function

Private Function BindProduct() As DataTable

Dim objSQL As New SqlDataProvider

Dim objBind As DataTable = objSQL.FillTable("Pro_ProductByCategory")

Return objBind

End Function

#End Region

#Region "Event Handles"

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

Try

If Page.IsPostBack = False Then

End If

Catch ex As Exception

End Try

End Sub

Private Sub ucZedGraph_RenderGraph1(ByVal z As ZedGraph.Web.ZedGraphWeb, ByVal g As System.Drawing.Graphics, ByVal masterPane As ZedGraph.MasterPane) Handles ZedGraphWeb1.RenderGraph

Dim myPane As GraphPane = masterPane(0)

Dim myCurve As BarItem

Dim objBind As New DataTable

Dim ObjectName As String = ""

Dim dRow As DataRow

Dim i As Integer = 0

objBind = BindCategories()

If Not objBind Is Nothing Then

If objBind.Rows.Count > 0 Then

ReDim Labels(objBind.Rows.Count - 1)

ReDim XAxis(objBind.Rows.Count - 1)

For i = 0 To UBound(Labels)

dRow = objBind.Rows(i)

ObjectName = dRow("CategoryName")

If ObjectName <> "" Then

Labels(i) = ObjectName

End If

If Not Labels Is Nothing Then

objBind = BindProduct()

i = 0

If objBind.Rows.Count > 0 Then

For Each row As DataRow In objBind.Rows

If Not row Is Nothing Then

XAxis(i) = row("TotalNumber")

i = i + 1

End If

'Set the title Chart

myPane.Title.Text = "Horizontal Bars Charts"

myPane.Title.FontSpec.FontColor = Color.Blue

myPane.Title.FontSpec.Size = 14.0F

'Set the title and axis labels

'axis X

myPane.XAxis.Title.Text = "Number"

myPane.XAxis.Title.FontSpec.Size = 12.0F

'axis Y

myPane.YAxis.Title.Text = "Category"

myPane.YAxis.Title.FontSpec.Size = 12.0F

'axis X

myCurve = myPane.AddBar("", XAxis, Nothing, Color.Blue)

' Fill the bar with a Blue-white-Blue color gradient for a 3d look

myCurve.Bar.Fill = New Fill(Color.Green, Color.White, Color.Green, 90.0F)

'axis X

myPane.YAxis.Scale.TextLabels = Labels

myPane.YAxis.Scale.AlignH = AlignH.Right

' Set the XAxis to Text type

myPane.YAxis.Type = AxisType.Text

' Make the bars Vertical by setting the BarBase to "X"

myPane.BarSettings.Type = BarType.Cluster

myPane.BarSettings.Base = BarBase.Y

'Set Font Value for Axis

myPane.YAxis.Scale.FontSpec.Size = 8.0F

myPane.XAxis.Scale.FontSpec.Size = 8.0F

' Fill the axis background with a color gradient

myPane.Chart.Fill = New Fill(Color.White, Color.FromArgb(255, 255, 166), 45.0F)

masterPane.AxisChange(g)

End Sub

#End Region

End Class

End Namespace

Bây giờ chạy Project bạn sẽ có kết quả sẽ giống như hình dưới.

Chúc các bạn thành công!

Quang Bình

News Ticker