VB.net圖表控件和sql server

Question

問題：我目前使用vb應用程序（Visual Studio 2012）查詢我的數據庫（SQL Server 2012）並使用vb.net中的圖表控制功能顯示信息。

附加信息：我希望x軸顯示位置名稱和y軸以顯示位置的計數 我已經編寫了代碼，似乎無法找到代碼行中的錯誤。請找到下面的代碼！

代碼：

我的代碼如下：

Dim cnn3 As New SqlConnection 
    Dim cmd3 As New SqlCommand 

    cnn3.ConnectionString = ("Data Source=SARAHSCOMPUTER;Initial Catalog=FYPDB1;Integrated Security=True") 
    cmd3.Connection = cnn3 

    Dim tblFields As String = "SELECT * from tblTagInfo" 
    Dim oData As New SqlDataAdapter(tblFields, cnn3) 
    Dim ds As New DataSet 
    Dim oCmd As New SqlCommand(tblFields, cnn3) 


    cnn3.Open() 
    oData.Fill(ds, "tblTagInfo") 
    cnn3.Close() 

    Chart1.DataSource = ds.Tables("tblTagInfo") 
    Dim Series1 As Series = Chart1.Series("Series1") 
    Series1.Name = "Location" 
    Chart1.Series(Series1.Name).XValueMember = "Location" 
    Chart1.Series(Series1.Name).YValueMembers = "SELECT COUNT (Area) FROM tblLocation group by Location" 

    Chart1.Size = New System.Drawing.Size(780, 350) 
End Sub 

Answer 1

請試試這個代碼：

Dim cnn3 As New SqlConnection 
Dim cmd3 As New SqlCommand 

cnn3.ConnectionString = ("Data Source=SARAHSCOMPUTER;Initial Catalog=FYPDB1;Integrated Security=True") 
cmd3.Connection = cnn3 

Dim tblFields As String = "SELECT COUNT(Location) AS LocationCount, Location AS LocationName FROM tblTagInfo group by Location" 
Dim oData As New SqlDataAdapter(tblFields, cnn3) 
Dim ds As New DataSet 
Dim oCmd As New SqlCommand(tblFields, cnn3) 


cnn3.Open() 
oData.Fill(ds, "tblTagInfo") 
cnn3.Close() 

Chart1.DataSource = ds.Tables("tblTagInfo") 
Dim Series1 As Series = Chart1.Series("Series1") 
Series1.Name = "Sales" 
Chart1.Series(Series1.Name).XValueMember = "LocationName" 
Chart1.Series(Series1.Name).YValueMembers = "LocationCount" 

Chart1.Size = New System.Drawing.Size(780, 350)