Here is a small function to return the GUID.
GUID stands for Globally Unique Identifiers. GUIDs are 128-bit globally unique identifiers and they are generated automatically based on close to two zillion frequently varying factors.
It has extremely low possibility that a generated GUID would equal to another GUID.
Function GenerateGUID() as string
return System.Guid.NewGuid.ToString()
End function
Here is a simple way of storing applications settings.
In your Visual Studio Project open the settings.
When you click on the Settings as shown in Step 1, you would get the following screen.
You can create your settings as shown below by providing your customised values in the Value column as shown below
Here is how you will use those values in your project .
If you would like to hide the columnheaders of a datagridview in your winforms application then here is the code for that.
‘ This will hide all the column headers for your datagridview
In VB.NET use this code
DataGridView1.ColumnHeadersVisible = False
In C# use the following code
dataGridView1.ColumnHeadersVisible = false;To get the list of installed printers on your computer use the following code which will populate a Combo box with the list of installed printers.
Private Sub PopulateInstalledPrintersCombo() ' Add list of installed printers found to the combo box. ' The pkInstalledPrinters string will be used to provide the display string. Dim i As Integer Dim pkInstalledPrinters As String For i = 0 To Printing.PrinterSettings.InstalledPrinters.Count - 1 pkInstalledPrinters = Printing.PrinterSettings.InstalledPrinters.Item(i) comboInstalledPrinters.Items.Add(pkInstalledPrinters) Next End Sub
Learn how to printer address labels on Dymo Label Printer in VB.NET
There are numerous example for C3 but I had to spend quite some time to adapt it to my project using VB.NET
Hope it can be of help to you.
I assume that you have
already added the GridMVC package from NUGET.
Here are step by step guide
Controller
No change needed , see a sample below,
Function Index() As ActionResult
Return View(db.Categories.ToList())
End Function
View
Add the following import at the top of your view
@imports GridMVC.html
You would need to reference the following also
Add the stylesheets (check the location after you install the GridMVC package)
<link href=”~/Content/Gridmvc.css” rel=”stylesheet” />
<link href=”~/Content/gridmvc.datepicker.min.css” rel=”stylesheet” />
For your paging support
Install the PagedList package also
Once you have installed this package then add the following reference to your view, this will help you format your paging buttons
properly.
<link href=”~/Content/PagedList.css” rel=”stylesheet” />
Add the following code for your Grid to appear – In the following examples my Model has three fields – CatId, CatName
and ParentCatId. Make changes to suit your needs.
@Html.Grid(Model).Columns(Function(columns)
columns.Add(Function(o) o.CatID).Titled(“Cat #“).SetWidth(40)
columns.Add(Function(o) o.CatName).Titled(“Category“).SetWidth(100)
columns.Add(Function(o) o.ParentCatID).Titled(“Parent Cat #“).SetWidth(40)
End Function
).WithPaging(10).Sortable(True)
How to allow File Downloads in MVC4 using VB.NET
We are using an ActionResult instead of FileResult.
Function download(id as Integer) As ActionResult
The reason is that if use the FileResult and your file does not exist then it will show a blank page, instead of this
we are using an ActionResult which is more versatile.
We can return the actual FileResult if the file exists
and in case of an error we can return a View (if we used a FileResult
Function download(id as Integer) As ActionResult
‘ In this example we are using the id to pick up the actual file from a model
Dim SoundFile as SoundFile = db.SoundFiles.Find(id)
Dim path As String = Server.MapPath(“~/myLocation/” & SoundFile.MP3File)
‘get file object as FileInfo
Dim fileinfo As System.IO.FileInfo = New System.IO.FileInfo(path)‘– if the file exists on the server
If fileinfo.Exists Then
rep.IncrementDownloadCount(id) ‘This is my routine to count the downloads, you will not need it
Return File(path, “application/octet-stream”, fileinfo.Name)
Else
Return View(“Error”)
End IfEnd Function
If you are using the Twitter Bootsrap in you MVC4 project and you have a need to display a boostrap button then here is a simple way to use it with the @html.actionlink
@Html.ActionLink(“download”, “download”, New With {.rid = Model.RingID}, New With {.class = Html.Raw(“btn btn-primary btn-mini”)})
Here is a simple code snippet to loop through the records in VB.NET using LINQ
The following code example takes the records from an Entity Framework Model named as Video and then allows to loop through each record.
Dim List As List(Of Video)
List = (From video In db.Videos Order By video.ID Descending).ToList
For Each item In List
Debug.Print(item.CategoryID)
Debug.Print(item.VideoName)
Next
There is often a need to pass a variable from one Winform to another.
There are two scenarios
Let us say you have two forms
1. You opened Form1 and then you want to open a new form called Form2 and you would want to carry some information from Form 1 to Form2.
The user has typed the Employee name JOHN in the text box on the first form and then clicked on the Lookup Dept. This openes the second lookup form (Form2) where the user can select a Dept Name.
Notice that on the Form2 we have the Employee Name shown ( form1 opened form2 and passed the value of EmployeeName)
2. You have Form1 and Form2 already open and you want to pass a variable from Form2 to Form1
Once we select the Dept B on the Form 2 we click on Select and close. The second form (Form2) closes and the value of the selected department Dept B is passed back to the First form (Form1)
Here is the code for the Form1
Public Class Form1
WithEvents fr As New Form2 ‘ Declare the new form using WithEvents
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
fr.lblEmployeeName.Text = Me.TextBox1.Text ‘ Send the value of Textbox1 to the second Form
fr.Show()
End SubPrivate Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
End Sub
Private Sub fr_GetDepartment() Handles fr.GetDepartment ‘ This is the new Event which has been declared and raised from Second Form
Me.TextBox2.Text = fr.ListBox1.SelectedItem.ToString ‘ The Listbox selected item value has been received from the second form
End Sub
End Class
Here is the code for Form2
Public Class Form2
Event GetDepartment() ‘ You declare this Event for this Form which can be trapped from Form1
Private Sub Form2_Load(sender As Object, e As EventArgs) Handles MyBase.Load
With Me.ListBox1
.Items.Add(“Dept A”)
.Items.Add(“Dept B”)
.Items.Add(“Dept C”)
End With
End SubPrivate Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
RaiseEvent GetDepartment() ‘ We raise the event here in Form2 which will provide you an opportunity to trap it in Form1
Me.Close()
End Sub
End Class
A Combo box has two properties
1.One which displays the items in the combo box called the DISPLAY MEMBER
2. Another one which stores the underlying ID for the Item which is being Displayed.
eg your table may have EmployeeId and EmployeeName.
You would like to display the EmployeeName in the ComboBox and when a user selects an employee name you would like to save the EmployeeID.
Function Fillcombo(ByVal SQL As String, ByVal CBO As ComboBox, ByVal DisplayMember As String, ByVal ValueMember As String)
Dim dt As New DataTable 'Create a New DataTable
Dim dc As New SqlCommand 'Create a New SQLCommand
Dim da As New SqlDataAdapter ' Create a New SQL Data Adapter
dc.CommandTimeout = 0
dc.CommandText = sql
da.SelectCommand = dc
dc.Connection = cn
da.Fill(dt) ‘ Use the DataAdapter to fill the DataTable with the records
Try
CBO.DataSource = dt
CBO.DisplayMember = DisplayMember ‘ This is the item which will be displayed on the combo box eg Employee Name
CBO.ValueMember = ValueMember ‘ This is the value which is stored eg. employeeID
Catch
MsgBox(“Unable to Fill the Combobox:” & CBO.Name & ” with values” & “:” & Err.Description)
End Try
End Function
How to use the above function
Fillcombo(“Select EmployeeID,EmployeeName from Employees”, Me.EmployeeCombo, “EmployeeName”, “EmployeeID”)