How do I check if a string contains only alphabetic characters in JavaScript using regular expressions?
Ava W

To check if a string contains only alphabetic characters in JavaScript using regular expressions, you can follow these steps: 1. Use thetest() method of theRegExp object to check if the string matches a regular expression pattern. 2. Construct a regular expression pattern that matches only alphabetic characters. You can use the regular expression pattern/^[a-zA-Z]+$/ to match uppercase and lowercase letters. -^ asserts the start of the string. -[a-zA-Z] matches any uppercase or lowercase letter. -+ matches one or more occurrences of the preceding pattern. -$ asserts the end of the string. 3. Call thetest() method on the regular expression pattern, passing the string as an argument. - Thetest() method returnstrue if the string matches the pattern, indicating that it contains only alphabetic characters. - Thetest() method returnsfalse if the string does not match the pattern, indicating that it contains non-alphabetic characters. Here's an example implementation:

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function isAlphabetic(str) {
  const pattern = /^[a-zA-Z]+$/;
  return pattern.test(str);
}

You can then use theisAlphabetic() function to check if a string contains only alphabetic characters. Here are some examples:

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console.log(isAlphabetic('Hello'));   // Output: true
console.log(isAlphabetic('123'));     // Output: false
console.log(isAlphabetic('Abc123'));  // Output: false

In this example, theisAlphabetic() function takes a stringstr as input and returnstrue if the string contains only alphabetic characters, andfalse otherwise. By using the regular expression pattern/^[a-zA-Z]+$/ and thetest() method, you can easily check if a string contains only alphabetic characters.