Unicode C

Regular Expression Replace Full Matches

See more Regular Expressions Examples

Demonstrates replacing the full matches of a regular expression.

Note: Chilkat uses PCRE2. See PCRE2 Regular Expressions
Also see: PCRE2 Performance

Unicode C

#include <C_CkStringBuilderW.h>
#include <C_CkJsonObjectW.h>

void ChilkatSample(void)
    {
    BOOL success;
    const wchar_t *subject;
    const wchar_t *pattern;
    HCkStringBuilderW sb;
    HCkJsonObjectW json;
    int timeoutMs;
    int numMatches;
    HCkStringBuilderW sbTemp;
    int i;

    success = FALSE;

    success = FALSE;

    subject = L"John Anders, +_+_+ Mary Robins $$$$";
    pattern = L"\\w+\\s+\\w+";

    sb = CkStringBuilderW_Create();
    CkStringBuilderW_Append(sb,subject);

    json = CkJsonObjectW_Create();
    CkJsonObjectW_putEmitCompact(json,FALSE);

    timeoutMs = 2000;
    numMatches = CkStringBuilderW_RegexMatch(sb,pattern,json,timeoutMs);
    if (numMatches < 0) {
        // Probably an error in the regular expression.
        // Suggestion: Use AI to help create and/or diagnose regular expressions.
        wprintf(L"%s\n",CkStringBuilderW_lastErrorText(sb));
        CkStringBuilderW_Dispose(sb);
        CkJsonObjectW_Dispose(json);
        return;
    }

    // Examine the matches:
    wprintf(L"%s\n",CkJsonObjectW_emit(json));

    // {
    //   "match": [
    //     {
    //       "group": [
    //         {
    //           "cap": "John Anders",
    //           "idx": 0,
    //           "len": 11
    //         }
    //       ]
    //     },
    //     {
    //       "group": [
    //         {
    //           "cap": "Mary Robins",
    //           "idx": 19,
    //           "len": 11
    //         }
    //       ]
    //     }
    //   ]
    // }

    sbTemp = CkStringBuilderW_Create();

    i = 0;
    numMatches = CkJsonObjectW_SizeOfArray(json,L"match");
    while (i < numMatches) {

        CkJsonObjectW_putI(json,i);

        // The full match is always in group 0.
        CkStringBuilderW_Clear(sbTemp);
        CkJsonObjectW_StringOfSb(json,L"match[i].group[0].cap",sbTemp);

        // Indicate that we wish to replace the full match with it's value converted to uppercase.
        CkStringBuilderW_ToUppercase(sbTemp);
        CkJsonObjectW_UpdateSb(json,L"match[i].group[0].rep",sbTemp);

        i = i + 1;
    }

    // The JSON now has replacement strings:
    wprintf(L"%s\n",CkJsonObjectW_emit(json));

    // {
    //   "match": [
    //     {
    //       "group": [
    //         {
    //           "cap": "John Anders",
    //           "idx": 0,
    //           "len": 11,
    //           "rep": "JOHN ANDERS"
    //         }
    //       ]
    //     },
    //     {
    //       "group": [
    //         {
    //           "cap": "Mary Robins",
    //           "idx": 19,
    //           "len": 11,
    //           "rep": "MARY ROBINS"
    //         }
    //       ]
    //     }
    //   ]
    // }

    // Call RegexReplace to update the StringBuilder with the replacements.
    success = CkStringBuilderW_RegexReplace(sb,json);
    if (success == FALSE) {
        wprintf(L"%s\n",CkStringBuilderW_lastErrorText(sb));
        CkStringBuilderW_Dispose(sb);
        CkJsonObjectW_Dispose(json);
        CkStringBuilderW_Dispose(sbTemp);
        return;
    }

    wprintf(L"Result after doing replacements:\n");
    wprintf(L"%s\n",CkStringBuilderW_getAsString(sb));

    // Result after doing replacements:
    // JOHN ANDERS, +_+_+ MARY ROBINS $$$$


    CkStringBuilderW_Dispose(sb);
    CkJsonObjectW_Dispose(json);
    CkStringBuilderW_Dispose(sbTemp);

    }