sparkydarky <markdueck.bz@gmail.com> wrote:

> I have a bunch of strings in a database that have in them a number I
> want to extract. Here's the example code I've been working with:
>
> AnsiString tmp = "AMjsdfdsdfj 457756 some description";

What is an "AnsiString"?

> int firstDelim = 0;
> int secondDelim = 0;
>
> for(int i=0; i<=tmp.Length(); i++)
> {

What exactly does "IsDelimiter" do?

> if(IsDelimiter(" ", tmp, i));
> {
> if ( firstDelim == 0 )
> firstDelim = i;
> else
> {
> secondDelim = i;
> break;
> }
> }
> if ( secondDelim > 0 )
> break;
> }
> int str_length = secondDelim - firstDelim;
> ShowMessage(tmp.SubString(firstDelim, str_length));
>
> Can someone give me a hint how to get this to work?

I'm not entirely sure what you think the above should do in the first
place. You leave a lot to be assumed... My assumptions: the various
parts of the string are separated by at least one space character, that
AnsiString can be inserted into a stringstream, and that you only want
to extract the first number in the string... There might be some other
assumptions I didn't think of.

int extractNumber( const string& str )
{
int result = 0;
stringstream ss( str );
while ( !( ss >> result ) ) {
if ( !ss.eof() ) {
ss.clear();
ss.ignore( numeric_limits<streamsize>::max(), ' ' );
}
else {
throw runtime_error( "no number" );
}
}
return result;
}

What the code does. Put the string into a stringstream, then attempt to
extract a number from it. For as long as we can't extract a number: if
we aren't at the end of the stream, clear the stream, scan to the next
space, and try again. Otherwise, throw an error indicating that no
number was found.