How Can I Ensure My Regular Expression Matches the Entire Input String?

The full text matching skills of regular expression

To match the entire string with regular expressions, you need to ensure that the mode matches the entire input string. The following methods can be achieved:

<.> 1. Use^and $ anchor points:

^"and" $ "represent the beginning and end of the string, respectively. For example, "^Red October $" (not distinguished by the case) ensures that the regular expression only matches the entire string that is completely equal to "Red October". <.> 2. Use the character class (square bracket representation):

The characters to be matched are included in square brackets, such as '[aa] BCD' matching 'abcd' or 'abcd'. If the entire string is included with square brackets, such as '^[Red October] $', ensure that there are no other characters before and after the string. It should be noted that the actual effect of this method is similar to using anchor points, but the expression is different.

<.> 3. Avoid partial matching:

The regular expression is allowed to be partially matched by default. To avoid this, you can use the "" limited character to indicate that a character or group must match it once or multiple times. For example, "^Red October $" only matches a string containing "Red October" without any other characters. Similarly, this method is similar to the anchor point method, but the expression is more concise when processing the string that may contain duplicate characters.

Through the above methods, you can ensure that the regular expression only matches the entire input string to avoid partial matching.

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