instance method String#startsWith

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String#startsWith(substring[, position]) → Boolean
  • substring (String): The characters to be searched for at the start of this string.
  • [position] (Number): The position in this string at which to begin searching for substring; defaults to 0.

Checks if the string starts with substring.

String#startsWith acts as an ECMAScript 6 polyfill. It is only defined if not already present in the user's browser, and it is meant to behave like the native version as much as possible. Consult the ES6 specification for more information.

'Prototype JavaScript'.startsWith('Pro');
//-> true
'Prototype JavaScript'.startsWith('Java', 10);
//-> true