Visual FoxPro Requires Chilkat v11.1.0+

Regular Expression with Multiple Matches and Capture Groups

See more Regular Expressions Examples

Demonstrates a regular expression with multiple matches and capture groups for each match.

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

Visual FoxPro

LOCAL lnSuccess
LOCAL lcPattern
LOCAL loSb
LOCAL lnCrlf
LOCAL loJson
LOCAL lnTimeoutMs
LOCAL lnNumMatches
LOCAL lcCap
LOCAL i
LOCAL lnMatchCount
LOCAL j
LOCAL lnNumCaptureGroups

lnSuccess = 0

lcPattern = "Name:\s+(\w+)\s+(\w+),\s+Email:\s+(\S+)"

loSb = CreateObject('Chilkat.StringBuilder')
lnCrlf = 1
loSb.AppendLine("Name: John Smith, Email: john.smith@example.com",lnCrlf)
loSb.AppendLine("Name: Jack Johnson, Email: jack.johnson@example.com",lnCrlf)
loSb.AppendLine("Name: Mary Adams, Email: mary.adams@example.com",lnCrlf)

? loSb.GetAsString()

*  We have the following string:
*  Name: John Smith, Email: john.smith@example.com
*  Name: Jack Johnson, Email: jack.johnson@example.com
*  Name: Mary Adams, Email: mary.adams@example.com

loJson = CreateObject('Chilkat.JsonObject')
loJson.EmitCompact = 0

lnTimeoutMs = 2000
lnNumMatches = loSb.RegexMatch(lcPattern,loJson,lnTimeoutMs)
IF (lnNumMatches < 0) THEN
    *  Probably an error in the regular expression.
    *  Suggestion: Use AI to help create and/or diagnose regular expressions.
    ? loSb.LastErrorText
    RELEASE loSb
    RELEASE loJson
    CANCEL
ENDIF

*  Examine the matches:
? loJson.Emit()

*  This is the JSON with the match information.
*  See the JSON parsing code below to get the matched capture group values.

*  {
*    "match": [
*      {
*        "group": [
*          {
*            "cap": "Name: John Smith, Email: john.smith@example.com",
*            "idx": 0,
*            "len": 47
*          },
*          {
*            "cap": "John",
*            "idx": 6,
*            "len": 4
*          },
*          {
*            "cap": "Smith",
*            "idx": 11,
*            "len": 5
*          },
*          {
*            "cap": "john.smith@example.com",
*            "idx": 25,
*            "len": 22
*          }
*        ]
*      },
*      {
*        "group": [
*          {
*            "cap": "Name: Jack Johnson, Email: jack.johnson@example.com",
*            "idx": 49,
*            "len": 51
*          },
*          {
*            "cap": "Jack",
*            "idx": 55,
*            "len": 4
*          },
*          {
*            "cap": "Johnson",
*            "idx": 60,
*            "len": 7
*          },
*          {
*            "cap": "jack.johnson@example.com",
*            "idx": 76,
*            "len": 24
*          }
*        ]
*      },
*      {
*        "group": [
*          {
*            "cap": "Name: Mary Adams, Email: mary.adams@example.com",
*            "idx": 102,
*            "len": 47
*          },
*          {
*            "cap": "Mary",
*            "idx": 108,
*            "len": 4
*          },
*          {
*            "cap": "Adams",
*            "idx": 113,
*            "len": 5
*          },
*          {
*            "cap": "mary.adams@example.com",
*            "idx": 127,
*            "len": 22
*          }
*        ]
*      }
*    ]
*  }

*  Important:  Capture group 0 always contains the entire match — that is, the portion of the input string that matches the full regular expression.

i = 0
lnMatchCount = loJson.SizeOfArray("match")
DO WHILE i < lnMatchCount
    ? "Match " + STR(i + 1) + ":"
    loJson.I = i
    j = 0
    lnNumCaptureGroups = loJson.SizeOfArray("match[i].group")
    DO WHILE j < lnNumCaptureGroups
        loJson.J = j
        lcCap = loJson.StringOf("match[i].group[j].cap")
        ? STR(j) + ": " + lcCap
        j = j + 1
    ENDDO
    i = i + 1
ENDDO

*  Capture group 0 always contains the entire match — that is, the portion of the input string that matches the full regular expression.

*  Output

*  Match 1:
*  0: Name: John Smith, Email: john.smith@example.com
*  1: John
*  2: Smith
*  3: john.smith@example.com
*  Match 2:
*  0: Name: Jack Johnson, Email: jack.johnson@example.com
*  1: Jack
*  2: Johnson
*  3: jack.johnson@example.com
*  Match 3:
*  0: Name: Mary Adams, Email: mary.adams@example.com
*  1: Mary
*  2: Adams
*  3: mary.adams@example.com

RELEASE loSb
RELEASE loJson