It works with ASCII characters in versions 2.0 through 2.9. This feature works with Unicode characters in versions 3.0 and later this flavor. Earlier versions do not support it at all. This feature works with Unicode characters in versions 3.0 and later of this flavor. This feature works with ASCII characters only in all versions of this flavor. This feature works with the characters in the active code page in all versions of this flavor. This feature works with Unicode characters in all versions of this flavor. Earlier and later versions do not support it. Only versions 2.0 through 2.9 supports this feature. Version 3.0 and all later versions of this flavor support this feature. YESĪll versions of this flavor support this feature. You can change the flavors using the drop-down lists above the table. The final two columns indicate whether your two chosen regular expression flavors support this particular feature. If the syntax has variable elements, the syntax is described.įunctional regular expression that demonstrates the feature. If the syntax is fixed, it is simply shown as such. The actual regex syntax for this feature.
The name of the feature, which also serves as a link to the relevant section in the tutorial. The tables have six columns for each regular expression feature.
To get the most out of them, follow this legend to learn how to read them. The reference tables pack an incredible amount of information. RegExr - useful for testing whether your regular expression is valid.The regular expressions reference on this website functions both as a reference to all available regex syntax and as a comparison of the features supported by the regular expression flavors discussed in the tutorial.The following list contains additional resources for more information about using RegEx:
+ as a quantifier instead of the literal plus sign character. If the + sign is not escaped with a backslash, RegEx treats The following table gives an example on how to escape a reserved metacharacter when searching. When using RegEx to search for a character that is a reserved metacharacter, use the backslash \ to escape the character so it can be recognized. RegEx: only permits for 2Ĭharacter, or character group, occurs at least n times, and at most m times.ĭigit, thus outside of the character range.Pattern: 4 letters-4 digits-4 letters-4 digits.
This single RegEx returns any document that contains any of the three serial numbers. Instead of writing three literal search strings to match each serial number, you can construct one regular expression to match the serial numbers’ pattern. For example, the following serial numbers: RegEx can help you in cases where you need to find different numbers that contain the same pattern.