Flutter replaces html tags in strings

replaceAll method

Regular expressions andreplaceAllMethod to replace HTML tags in strings. Here is a sample code:

String html = "<p>Hello, <a href="" rel="external nofollow" >world!</a></p>";
String plainText = (RegExp(r'<[^>]*>|&[^;]+;'), ''); // Replace HTML tags and entity references with regular expressionsprint(plainText); // Output: Hello, world!

In the example above, we first define a string containing HTML tags.

Then, we usereplaceAllMethods replace HTML tags and entity references.

In regular expressions,<[^>]*>Match any HTML tags,&[^;]+;Match entity references.

Finally, we output the plain text string "Hello, world!".

Regular expressions are a flexible text matching tool and are also widely used in Flutter, such as verification of user input, data processing, etc.

Regular expressions are usually created using the RegExp class and can be matched with strings. Here are some examples for creating and using regular expressions:

Basic syntax

useRegExpThe class creates a regular expression object and useshasMatchMethod checks whether the string matches the regular expression.

String input = 'abc123';
RegExp regex = RegExp(r'[a-z]+[0-9]+'); // Match letters and numbersif ((input)) {
  print('Match!');
} else {
  print('No match.');
}

Extract the matching part

usefirstMatchGet the first matching part of the string, and useallMatchesGet all matching parts. Here is an example that uses a regular expression to extract numbers from a string:

String input = 'abc123def456';
RegExp regex = RegExp(r'\d+'); // Match numbersIterable<Match> matches = (input);
for (Match match in matches) {
  String number = (0);
  print(number);
}

Replace the matching part

usereplaceAllMethod replaces the matching part of the string. Here is an example that replaces words in a string using regular expressions:

String input = 'hello world';
RegExp regex = RegExp(r'\b\w+\b'); // Match wordsString result = (regex, 'Flutter');
print(result); // Output: Flutter Flutter

These are just basic examples of using regular expressions in Flutter. In practice, you can use more complex regular expressions to handle more complex strings.

The above is the detailed content of the html tag in the Flutter replacement string. For more information about the Flutter replacement string html, please follow my other related articles!