::IsNumber() returned FALSE if a + or - sign was the first character of the string. "-123" should be considered a number

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@6250 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/string.cpp

@@ -910,6 +910,8 @@ bool wxString::IsWord() const
 bool wxString::IsNumber() const
 {
   const wxChar *s = (const wxChar*) *this;
+  if (wxStrlen(s))
+     if ((s[0] == '-') || (s[0] == '+')) s++;
   while(*s){
     if(!wxIsdigit(*s)) return(FALSE);
     s++;