Breaking/exit nested for in vb.net

How do I get out of nested for or loop in vb.net?

I tried using exit for but it jumped or breaked only one for loop only.

How can I make it for the following:

for each item in itemList
     for each item1 in itemList1
          if item1.text = "bla bla bla" then
                exit for
          end if
     end for
end for

Unfortunately, there's no exit two levels of for statement, but there are a few workarounds to do what you want:

Goto. In general, using goto is considered to be bad practice (and rightfully so), but using goto solely for a forward jump out of structured control statements is usually considered to be OK, especially if the alternative is to have more complicated code.
```
For Each item In itemList
    For Each item1 In itemList1
        If item1.Text = "bla bla bla" Then
            Goto end_of_for
        End If
    Next
Next

end_of_for:
```

Dummy outer block

Do
    For Each item In itemList
        For Each item1 In itemList1
            If item1.Text = "bla bla bla" Then
                Exit Do
            End If
        Next
    Next
Loop While False

Try
    For Each item In itemlist
        For Each item1 In itemlist1
            If item1 = "bla bla bla" Then
                Exit Try
            End If
        Next
    Next
Finally
End Try

Separate function: Put the loops inside a separate function, which can be exited with return. This might require you to pass a lot of parameters, though, depending on how many local variables you use inside the loop. An alternative would be to put the block into a multi-line lambda, since this will create a closure over the local variables.

Boolean variable: This might make your code a bit less readable, depending on how many layers of nested loops you have:

Dim done = False

For Each item In itemList
    For Each item1 In itemList1
        If item1.Text = "bla bla bla" Then
            done = True
            Exit For
        End If
    Next
    If done Then Exit For
Next

Put the loops in a subroutine and call return

Make the outer loop a while loop, and "Exit While" in the if statement.

I've experimented with typing "exit for" a few times and noticed it worked and VB didn't yell at me. It's an option I guess but it just looked bad.

I think the best option is similar to that shared by Tobias. Just put your code in a function and have it return when you want to break out of your loops. Looks cleaner too.

For Each item In itemlist
    For Each item1 In itemlist1
        If item1 = item Then
            Return item1
        End If
    Next
Next

Hitesh Paliwal

For i As Integer = 0 To 100
    bool = False
    For j As Integer = 0 To 100
        If check condition Then
            'if condition match
            bool = True
            Exit For 'Continue For
        End If
    Next
    If bool = True Then Continue For
Next

Poppa Mintin

If I want to exit a for-to loop, I just set the index beyond the limit:

    For i = 1 To max
        some code
        if this(i) = 25 Then i = max + 1
        some more code...
    Next`

Poppa.

来源：https://stackoverflow.com/questions/5312291/breaking-exit-nested-for-in-vb-net

标签

vb.net

for-loop

nested-loops