Update share output (#782)

* fix share bugs

* PR feedback

* PR feedback and merge fix

* Fix spacing and use explicit break

* Fix extra space

src/CalcViewModel/Common/Utils.cpp

@@ -264,6 +264,71 @@ void Utils::TrimBack(wstring& value)
     }).base(), value.end());
 }
 
+String^ Utils::EscapeHtmlSpecialCharacters(String^ originalString, shared_ptr<vector<wchar_t>> specialCharacters)
+{
+    // Construct a default special characters if not provided.
+    if (specialCharacters == nullptr)
+    {
+        specialCharacters = make_shared<vector<wchar_t>>();
+        specialCharacters->push_back(L'&');
+        specialCharacters->push_back(L'\"');
+        specialCharacters->push_back(L'\'');
+        specialCharacters->push_back(L'<');
+        specialCharacters->push_back(L'>');
+    }
+
+    bool replaceCharacters = false;
+    const wchar_t* pCh;
+    String^ replacementString = nullptr;
+
+    // First step is scanning the string for special characters.
+    // If there isn't any special character, we simply return the original string
+    for (pCh = originalString->Data(); *pCh; pCh++)
+    {
+        if (std::find(specialCharacters->begin(), specialCharacters->end(), *pCh) != specialCharacters->end())
+        {
+            replaceCharacters = true;
+            break;
+        }
+    }
+
+    if (replaceCharacters)
+    {
+        // If we indeed find a special character, we step back one character (the special
+        // character), and we create a new string where we replace those characters one by one
+        pCh--;
+        wstringstream buffer;
+        buffer << wstring(originalString->Data(), pCh);
+
+        for (; *pCh; pCh++)
+        {
+            switch (*pCh)
+            {
+            case L'&':
+                buffer << L"&amp;";
+                break;
+            case L'\"':
+                buffer << L"&quot;";
+                break;
+            case L'\'':
+                buffer << L"&apos;";
+                break;
+            case L'<':
+                buffer << L"&lt;";
+                break;
+            case L'>':
+                buffer << L"&gt;";
+                break;
+            default:
+                buffer << *pCh;
+            }
+        }
+        replacementString = ref new String(buffer.str().c_str());
+    }
+
+    return replaceCharacters ? replacementString : originalString;
+}
+
 bool operator==(const Color& color1, const Color& color2)
 {
     return equal_to<Color>()(color1, color2);

src/CalcViewModel/Common/Utils.h

@@ -430,6 +430,7 @@ namespace Utils
     void TrimFront(std::wstring& value);
     void TrimBack(std::wstring& value);
 
+    Platform::String ^ EscapeHtmlSpecialCharacters(Platform::String ^ originalString, std::shared_ptr<std::vector<wchar_t>> specialCharacters = nullptr);
 
 }