How to useRegular Expression (RegExp) in Javascript
Regular expressions provide a flexible way to match patterns within strings. We can use a regular expression pattern to check if a string starts with another string.
function startsWith(str, substr) {
// Escape special characters in the substring
const escapedSubstr = substr.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
// Create a regular expression pattern to match the start of the string
const pattern = new RegExp('^' + escapedSubstr);
// Test if the string matches the pattern
return pattern.test(str);
}
console.log(startsWith('Hello World', 'Hello')); // Output: true
console.log(startsWith('JavaScript', 'Script')); // Output: false
Output
true false
How to check if a string “StartsWith” another string in JavaScript ?
In JavaScript, the ‘startsWith()’ method is a built-in method that allows one to check whether a string starts with a specified substring.
Syntax: It takes a single argument, which is the substring we want to check whether the string starts with.
string.startsWith(searchString[, position])
Contact Us