NLS: Esempio di normalizzazione Unicode

L'applicazione di esempio descritta in questo argomento illustra la rappresentazione delle stringhe usando la normalizzazione Unicode.

L'applicazione di esempio chiama tutti e quattro i moduli di normalizzazione Unicode con la stessa stringa di input. Viene quindi effettuata una chiamata con Unicode non valido per illustrare il funzionamento dell'indice del codice carattere non valido. Infine, l'applicazione passa una stringa che si espande per essere anomalamente lunga, richiedendo più chiamate di normalizzazione di stringhe per ottenere una dimensione del buffer appropriata.

Questo esempio illustra le funzioni API NLS seguenti:

• IsNormalizedString
• NormalizeString

// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF 
// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO 
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A 
// PARTICULAR PURPOSE. 
// 
// Copyright (c) Microsoft Corporation. All rights reserved. 

// ============ Demonstration of Normalization APIs ============ 

#include "stdafx.h"
#include "windows.h"
#include <stdio.h>
#include <tchar.h>
#include "malloc.h"

// Print out a string using code points for the non-ASCII values 
void DumpString(LPWSTR pInput)
{
    while (*pInput != 0)
    {
        if (*pInput < 0x80)
            wprintf(L"%c", *pInput);
        else
            wprintf(L"\\x%4.4x", *pInput);
        pInput++;
    }
    wprintf(L"\n");
}

// Check if normalized and display normalized output for a particular normalization form 
void TryNormalization(NORM_FORM form, LPWSTR strInput)
{
    // Test if the string is normalized 
    if (IsNormalizedString(form, strInput, -1))
    {
        wprintf(L"Already normalized in this form\n");
    }
    else
    {
        // It was not normalized, so normalize it 
        int    iSizeGuess;
        LPWSTR pBuffer;

        // How big is our buffer (quick guess, usually enough) 
        iSizeGuess = NormalizeString(form, strInput, -1, NULL, 0);

        if (iSizeGuess == 0)
        {
            wprintf(L"Error %d checking for size\n", GetLastError());
        }

        while(iSizeGuess > 0)
        {
            pBuffer = (LPWSTR)malloc(iSizeGuess * sizeof(WCHAR));
            if (pBuffer)
            {
                // Normalize the string 
                int iActualSize = NormalizeString(form, strInput, -1, pBuffer, iSizeGuess);
                iSizeGuess = 0;
                if (iActualSize <= 0 && GetLastError() != ERROR_SUCCESS)
                {
                    // Error during normalization 
                    wprintf(L"Error %d during normalization\n", GetLastError());
                    if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
                    {
                        // If the buffer is too small, try again with a bigger buffer. 
                        wprintf(L"Insufficient buffer, new suggested buffer size %d\n", -iActualSize);
                        iSizeGuess = -iActualSize;
                    }
                    else if (GetLastError() == ERROR_NO_UNICODE_TRANSLATION)
                    {
                        wprintf(L"Invalid Unicode found at input character index %d\n", -iActualSize);
                    }
                }
                else
                {
                    // Display the normalized string 
                    DumpString(pBuffer);
                }

                // Free the buffer 
                free (pBuffer);
            }
            else
            {
                wprintf(L"Error allocating buffer\n");
                iSizeGuess = 0;
            }
        }
    }
}

int __cdecl wmain(int argc, WCHAR* argv[])
{
     // Tèst string ｔｏ nørmälize 
     LPWSTR strInput = L"T\u00e8st string \uFF54\uFF4F n\u00f8rm\u00e4lize";

    wprintf(L"Comparison of Normalization Forms, input string::\n");
    DumpString(strInput);

    // Try it in the 4 forms 
    wprintf(L"\n");
    wprintf(L"String in Form C:\n  ");
    TryNormalization(NormalizationC, strInput);

    wprintf(L"\n");
    wprintf(L"String in Form KC:\n  ");
    TryNormalization(NormalizationKC, strInput);

    wprintf(L"\n");
    wprintf(L"String in Form D:\n  ");
    TryNormalization(NormalizationD, strInput);

    wprintf(L"\n");
    wprintf(L"String in Form KD:\n  ");
    TryNormalization(NormalizationKD, strInput);

    // Note that invalid Unicode would show an error (illegal lone surrogate in this case) 
    wprintf(L"\n");
    wprintf(L"Attempt to normalize illegal lone surrogate:\n");
    TryNormalization(NormalizationC, L"Bad surrogate is here: '\xd800'");

    // Contrived strings can cause the initial size guess to be low 
    wprintf(L"\n");
    wprintf(L"Attempt to normalize a string that expands beyond the initial guess\n");
    TryNormalization(NormalizationC,
        // These all expand to 2 characters 
        L"\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958"
        L"\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958"
        L"\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958"
        L"\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958\u0958"
        // These all expand to 3 characters 
        L"\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c"
        L"\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c\ufb2c");
}