Save and Load

there are a few ways of doing this.

ahmedilyas at 2007-8-31 >

ok, taking in the first response....you need to open a file and write to it. you need to import the System.IO namespace, so declare it at the top of your class file (Code)

imports System.IO

Now, when the user presses, say, "Save" button, a click event will happen, in this event you would want to save the data to the file, so double click the button in designer view (where you create your form in the IDE) to create the event handler.

Next up, create the file:

Dim theStreamWriter as new StreamWriter(Application.StartupPath & "\myOutput.txt")

you are now creating a writer to write to the file specified, in the current directory of the application (where the application is running from: Application.StartupPath)

So now, you need to get your inputs and write to file. Next line of code would be something like:

theStreamWriter.WriteLine(Me.theTextBox.Text)

this will write, to the file, the text that is in the textbox on your form. The same thing happens when taking inputs from say, a combobox, or a listbox, or a label. you just need to find a way of getting its textual selected item/mode/property. So say if I had 3 textboxes, my lines of code:

theStreamWriter.WriteLine(Me.theTextBox1.Text)

theStreamWriter.WriteLine(Me.theTextBox2.Text)

theStreamWriter.WriteLine(Me.theTextBox3.Text)

would write to the file, the text in each of the textboxes specified. With me so far?

finally we need to close the file:

theStreamWriter.Close()

now to open the file:

If File.Exists(Application.StartupPath & "\myOutput.txt") then 'Check if the file exists before doing things

Dim theStreamReader as new StreamReader(Application.StartupPath & "\myOutput.txt")

'since we stored say, 3 lines in the file (for example) then we can read the 3 lines individually:

Me.theTextBox1.Text = theStreamReader.ReadLine()

Me.theTextBox2.Text = theStreamReader.ReadLine()

Me.theTextBox3.Text = theStreamReader.ReadLine()

theStreamReader.Close()

end if

This is an example, so be sure to modify to your needs. Be sure to implement error checking also. There are a few flaws already with this code but keeping it simple for now for you to understand/follow

ahmedilyas at 2007-8-31 >

Hi,

I am using similar code to save data from a datagrid to a text file. I manage to save the information but when I look at the text file, the chr(9), chr(10) and chr(13) shown as a "square" and all the data are in one line. Is there a way to save without the "square" on multiple line and with the "TAB" space?

This is the code to save my data. The "DataCache" is a datagrid. The output file must be a ".txt" file, I am creating an interface to read data from an hardware, so I need to respect the original structure of the file. I am using Visual Basic 2005 Express.

Dim DataRow As Integer = 0

Dim DataSaveString As String = ""

While DataRow <= 27

DataSaveString = DataSaveString + Me.DataCache.Item(0, DataRow).Value + ChrW(10)

DataSaveString = DataSaveString + Me.DataCache.Item(1, DataRow).Value + ChrW(10) + ChrW(13)

End While

Me.TempSaveField.Text = DataSaveString

File.WriteAllText("TestFile.txt", Me.TempSaveField.Text, TextEncoding)

End Sub

Draco3d at 2007-8-31 >