weird string problem

[Boni]

Dear all,

I need to replace in a long string all chr(10) to chr(10)chr(13) if 13 is
not behind 10.

dim str as string=....

If str.Chars(i) = vbLf And str.Chars(i + 1) <> vbCr Then

str.Insert(i, vbCr)

i = i + 1

End If

But if set a breakpoint on insert and look on str before and after insert I
can see, that vbCr is just not inserted!!! ascii(str.Chars(i) ) and
str.Chars(i+/-1) are not 13!!!

What is wrong??

Thanks,

Boni

[Chris Dunaway]

The answer is that strings are immutable, meaning they cannot change.
The insert method returns a new strings with your changes, therefore
you need to assign it back to your string variable:

str = str.Insert(i,vbCr)

[Boni]

Or noooo. Soo simple. I might need some sleep !
Thanks Chris
"Chris Dunaway" <du******@gmail.com> schrieb im Newsbeitrag
news:11**********************@f14g2000cwb.googlegr oups.com...

The answer is that strings are immutable, meaning they cannot change.
The insert method returns a new strings with your changes, therefore
you need to assign it back to your string variable:

str = str.Insert(i,vbCr)

[Dragon]

Hi,

String.Insert doesn't change the original string (as well as other
String methods), but generates a new
one instead.

So,
1. Use str = str.Insert(i,vbCr) - or -
2. Use StringBuilder for that.

BTW, have you considered using RegEx for this kind of job? It's pretty
simple:
str = System.Text.RegularExpressions.Regex.Replace(str, "\x0a(?!\x0d)",
Chr(10) & Chr(13))

Roman

[Boni]

Hi Dragon,
I was thinking about regexes, but my feeling was to avoid regexes for simple
things because of performance reasons. But as I see the building of temp
string objects seems to take time too. So I switch to regex. I don't think
that I will mention timing difference.

Thank you for an advice,
Boni
"Dragon" <[e-mail]> schrieb im Newsbeitrag
news:eF**************@TK2MSFTNGP14.phx.gbl...

Hi,

String.Insert doesn't change the original string (as well as other
String methods), but generates a new
one instead.

So,
1. Use str = str.Insert(i,vbCr) - or -
2. Use StringBuilder for that.

BTW, have you considered using RegEx for this kind of job? It's pretty
simple:
str = System.Text.RegularExpressions.Regex.Replace(str, "\x0a(?!\x0d)",
Chr(10) & Chr(13))

Roman