5 files changed, 18 insertions, 26 deletions
diff --git a/core/fpdftext/cpdf_textpagefind.cpp b/core/fpdftext/cpdf_textpagefind.cpp
index 7eaac35194..a4f4a6e828 100644
--- a/core/fpdftext/cpdf_textpagefind.cpp
+++ b/core/fpdftext/cpdf_textpagefind.cpp
@@ -348,15 +348,10 @@ bool CPDF_TextPageFind::IsMatchWholeWord(const CFX_WideString& csPageText,
     return false;
   }
   if (char_count > 0) {
-    if (csPageText.GetAt(startPos) >= L'0' &&
-        csPageText.GetAt(startPos) <= L'9' && char_left >= L'0' &&
-        char_left <= L'9') {
+    if (std::iswdigit(char_left) && std::iswdigit(csPageText.GetAt(startPos)))
       return false;
-    }
-    if (csPageText.GetAt(endPos) >= L'0' && csPageText.GetAt(endPos) <= L'9' &&
-        char_right >= L'0' && char_right <= L'9') {
+    if (std::iswdigit(char_right) && std::iswdigit(csPageText.GetAt(endPos)))
       return false;
-    }
   }
   return true;
 }
diff --git a/core/fxcrt/cfx_widestring.cpp b/core/fxcrt/cfx_widestring.cpp
index 2b98ce59a4..8cd4de6edd 100644
--- a/core/fxcrt/cfx_widestring.cpp
+++ b/core/fxcrt/cfx_widestring.cpp
@@ -10,6 +10,7 @@
 
 #include <algorithm>
 #include <cctype>
+#include <cwctype>
 
 #include "core/fxcrt/cfx_string_pool_template.h"
 #include "core/fxcrt/fx_basic.h"
diff --git a/core/fxcrt/fx_extension.cpp b/core/fxcrt/fx_extension.cpp
index 47bd937ff8..209584b68d 100644
--- a/core/fxcrt/fx_extension.cpp
+++ b/core/fxcrt/fx_extension.cpp
@@ -6,6 +6,8 @@
 
 #include "core/fxcrt/fx_extension.h"
 
+#include <cwctype>
+
 #if _FXM_PLATFORM_ == _FXM_PLATFORM_WINDOWS_
 #include <wincrypt.h>
 #else
@@ -67,11 +69,10 @@ float FXSYS_wcstof(const wchar_t* pwsStr, int32_t iLength, int32_t* pUsedLen) {
   float fValue = 0.0f;
   while (iUsedLen < iLength) {
     wchar_t wch = pwsStr[iUsedLen];
-    if (wch >= L'0' && wch <= L'9')
-      fValue = fValue * 10.0f + (wch - L'0');
-    else
+    if (!std::iswdigit(wch))
       break;
 
+    fValue = fValue * 10.0f + (wch - L'0');
     iUsedLen++;
   }
 
@@ -79,12 +80,11 @@ float FXSYS_wcstof(const wchar_t* pwsStr, int32_t iLength, int32_t* pUsedLen) {
     float fPrecise = 0.1f;
     while (++iUsedLen < iLength) {
       wchar_t wch = pwsStr[iUsedLen];
-      if (wch >= L'0' && wch <= L'9') {
-        fValue += (wch - L'0') * fPrecise;
-        fPrecise *= 0.1f;
-      } else {
+      if (!std::iswdigit(wch))
         break;
-      }
+
+      fValue += (wch - L'0') * fPrecise;
+      fPrecise *= 0.1f;
     }
   }
   if (pUsedLen)
diff --git a/core/fxcrt/fx_extension.h b/core/fxcrt/fx_extension.h
index e9d16786a9..00604fb22c 100644
--- a/core/fxcrt/fx_extension.h
+++ b/core/fxcrt/fx_extension.h
@@ -41,12 +41,8 @@ inline bool FXSYS_iswalpha(wchar_t wch) {
   return (wch >= L'A' && wch <= L'Z') || (wch >= L'a' && wch <= L'z');
 }
 
-inline bool FXSYS_iswdigit(wchar_t wch) {
-  return wch >= L'0' && wch <= L'9';
-}
-
 inline bool FXSYS_iswalnum(wchar_t wch) {
-  return FXSYS_iswalpha(wch) || FXSYS_iswdigit(wch);
+  return FXSYS_iswalpha(wch) || std::iswdigit(wch);
 }
 
 inline bool FXSYS_iswspace(wchar_t c) {
diff --git a/core/fxcrt/xml/cfx_xmlsyntaxparser.cpp b/core/fxcrt/xml/cfx_xmlsyntaxparser.cpp
index ac3f1b5c5d..e3d690f5ab 100644
--- a/core/fxcrt/xml/cfx_xmlsyntaxparser.cpp
+++ b/core/fxcrt/xml/cfx_xmlsyntaxparser.cpp
@@ -7,6 +7,7 @@
 #include "core/fxcrt/xml/cfx_xmlsyntaxparser.h"
 
 #include <algorithm>
+#include <cwctype>
 #include <iterator>
 
 #include "core/fxcrt/fx_extension.h"
@@ -633,20 +634,19 @@ void CFX_XMLSyntaxParser::ParseTextChar(wchar_t character) {
         if (iLen > 1 && csEntity[1] == L'x') {
           for (int32_t i = 2; i < iLen; i++) {
             w = csEntity[i];
-            if (w >= L'0' && w <= L'9') {
+            if (std::iswdigit(w))
               ch = (ch << 4) + w - L'0';
-            } else if (w >= L'A' && w <= L'F') {
+            else if (w >= L'A' && w <= L'F')
               ch = (ch << 4) + w - 55;
-            } else if (w >= L'a' && w <= L'f') {
+            else if (w >= L'a' && w <= L'f')
               ch = (ch << 4) + w - 87;
-            } else {
+            else
               break;
-            }
           }
         } else {
           for (int32_t i = 1; i < iLen; i++) {
             w = csEntity[i];
-            if (w < L'0' || w > L'9')
+            if (!std::iswdigit(w))
               break;
             ch = ch * 10 + w - L'0';
           }