ãëàâà 2 ðàçãëåäàõìå íà÷èíà íà ïîñòàâÿíå íà òî÷êè íà ïðåêúñâàíå è íà èçïîëçâàíå íà Äåáúãåðà (Debugger). Íåêà ðàçãëåäàìå ìàëêî ìåíþ Debug. Ìîæåòå äàïîâèêàòå ïðîçîðåö Exceptions íàïðèìåð (âèæ ôèãóðà 81) . Ìîæåòå äà ðàçãëåäàòå ÷åòèðèòå ãëàâíè ãðóïè èçêëþ÷åíèÿ.


Ôèãóðà 81

Àêî å èçáðàí îïöèîííèÿ áóòîí Break into the debugger, ìîæåòå äàïðîâåðèòå âñè÷êî è äà îáðàáîòèòå èçêëþ÷åíèåòî ñàìè. Àêî å èçáðàí îïöèîííèÿ áóòîí Continue, òàçè îïöèÿ ùå ïîçâîëè íà âàø ìàíèïóëàòîð íà èçêëþ÷åíèåòî äà îáðàáîòè ãðåøêàòà. Àêî å èçáðàí îïöèîííèÿ áóòîí Use parent setting, êîíêðåòíîòî èçêëþ÷åíèå ùå èçïîëçâà íàñòðîéêàòà èçáðàíà çà ðîäèòåëñêèÿ âúçåë.

Äà ðàçãëåäàìå ïðîãðàìà File System.

Òÿ å àïëèêàöèÿ ñ åäíà ôîðìà, íà êîÿòî èìà äâà êîíòðîëà: êîìàíäåí áóòîí Button1 è åòèêåò Label1. Êîäúò â êëàñà íà ôîðìàòà å:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim fw As New FileWork

fw.FileWorkMy()

End Sub


Private Sub Label1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label1.Click

Label1.Text = "InFile = ""c:SomeInFile.bin"" OutFile =""c:someOutFile.Bin"" "

End Sub

Èçïîëçâàéêè îò êîíòåêñòíîòî ìåíþ Add -Add Class, îòâàðÿìå ïðîçîðåöà ïîêàçàí íà ôèãóðà 82 è äîáàâÿìå ïðàçåí êëàñ FileWork.vb.

Ôèãóðà 82

Çàïèñâàìå ñëåäíèÿ êîä â íåãî:

Option Explicit On

Imports System.Windows.Forms

Imports System.IO

Imports System.Diagnostics

Imports System.Threading



Public Class FileWork




Sub FileWorkMy()

Dim OutFile As String

Dim InFile As String

InFile = "c:SomeInFile.bin"

OutFile = "c:someOutFile.Bin"

Dim outf As System.IO.File

Dim inf As System.IO.File

Dim x As Integer

Dim aRetVal As Integer

' ñúçäàâàíå íà ïîòîöè - streams çà âõîä - input è èçõîä - output

Dim myInstream As System.IO.FileStream

Dim myOutstream As System.IO.FileStream

Dim aFoo(100) As System.Byte ' äàííè çà ÷åòåíå è çàïèñ

For x = 1 To 99

aFoo(x) = x

Next

Try

myOutstream = outf.OpenWrite(OutFile) '"c:someOutFile.bin"

myOutstream.Flush()

For x = 1 To 11

myOutstream.Write(aFoo, 0, 10)

Next

myOutstream.Close()

myInstream = inf.OpenRead(OutFile) '"c:someInFile.bin"



aRetVal = myInstream.Read(aFoo, 0, 10) ' ÷åòå 10 áàéòà

MessageBox.Show(aRetVal)



Catch IOExcep As IO.IOException

'âúçíèêâà íÿêàêâà ãðåøêà. Èçâåæäàíå íà ñúîáùåíèå

`error message

MessageBox.Show(IOExcep.Message)

Finally

myInstream.Close() ' çàòâàðÿíå íà ôàéëîâåòå - files

End Try

End Sub

End Class


Ôèãóðà 83 Èçïúëíåíèå íà File System