Revert "Revert "Cleanup some numeric code.""

fpdfsdk/src/javascript/util.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "util.h"
 
 #include "../../include/javascript/IJavaScript.h"
 #include "JS_Context.h"
@@ skipping 407 matching lines @@
   for (int iIndex = 0; iIndex < (int)cFormat.size() && itSource < iSize;
        iIndex++) {
     char letter = cFormat[iIndex];
     switch (letter) {
       case '?':
         cPurpose += cSource[itSource];
         itSource++;
         break;
       case 'X': {
         while (itSource < iSize) {
-          if ((cSource[itSource] >= '0' && cSource[itSource] <= '9') ||
+          if (std::isdigit(cSource[itSource]) ||
               (cSource[itSource] >= 'a' && cSource[itSource] <= 'z') ||
               (cSource[itSource] >= 'A' && cSource[itSource] <= 'Z')) {
             cPurpose += cSource[itSource];
             itSource++;
             break;
           }
           itSource++;
         }
         break;
       } break;
       case 'A': {
         while (itSource < iSize) {
           if ((cSource[itSource] >= 'a' && cSource[itSource] <= 'z') ||
               (cSource[itSource] >= 'A' && cSource[itSource] <= 'Z')) {
             cPurpose += cSource[itSource];
             itSource++;
             break;
           }
           itSource++;
         }
         break;
       } break;
       case '9': {
         while (itSource < iSize) {
-          if (cSource[itSource] >= '0' && cSource[itSource] <= '9') {
+          if (std::isdigit(cSource[itSource])) {
             cPurpose += cSource[itSource];
             itSource++;
             break;
           }
           itSource++;
         }
         break;
       }
       case '*': {
         cPurpose.append(cSource, itSource, iSize - itSource);
@@ skipping 81 matching lines @@
   int iSize = params.size();
   if (iSize == 0)
     return FALSE;
   int nByte = params[0].ToInt();
   unsigned char cByte = (unsigned char)nByte;
   CFX_WideString csValue;
   csValue.Format(L"%c", cByte);
   vRet = csValue.c_str();
   return TRUE;
 }