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const sentence = "The quick brown fox jumps over the lazy dog.";
const word = "fox";
console.log(
`The word "${word}" ${
sentence.includes(word) ? "is" : "is not"
} in the sentence`,
);
// Expected output: "The word "fox" is in the sentence"
includes(searchString)
includes(searchString, position)
searchStringposition searchString 0
searchString true false
includes() false
"Blue Whale".includes("blue"); // false
"Blue Whale".toLowerCase().includes("blue"); // true
const str = "To be, or not to be, that is the question.";
console.log(str.includes("To be")); // true
console.log(str.includes("question")); // true
console.log(str.includes("nonexistent")); // false
console.log(str.includes("To be", 1)); // false
console.log(str.includes("TO BE")); // false
console.log(str.includes("")); // true
| ECMAScript 2027 LanguageSpecification # sec-string.prototype.includes |
StringString.prototype.anchor()String.prototype.at()String.prototype.big()String.prototype.blink()String.prototype.bold()String.prototype.charAt()String.prototype.charCodeAt()String.prototype.codePointAt()String.prototype.concat()String.prototype.endsWith()String.prototype.fixed()String.prototype.fontcolor()String.prototype.fontsize()String.prototype.includes()String.prototype.indexOf()String.prototype.isWellFormed()String.prototype.italics()String.prototype.lastIndexOf()String.prototype.link()String.prototype.localeCompare()String.prototype.match()String.prototype.matchAll()String.prototype.normalize()String.prototype.padEnd()String.prototype.padStart()String.prototype.repeat()String.prototype.replace()String.prototype.replaceAll()String.prototype.search()String.prototype.slice()String.prototype.small()String.prototype.split()String.prototype.startsWith()String.prototype.strike()String.prototype.sub()String.prototype.substr()String.prototype.substring()String.prototype.sup()String.prototype.toLocaleLowerCase()String.prototype.toLocaleUpperCase()String.prototype.toLowerCase()String.prototype.toString()String.prototype.toUpperCase()String.prototype.toWellFormed()String.prototype.trim()String.prototype.trimEnd()String.prototype.trimStart()String.prototype.valueOf()String.prototype[Symbol.iterator]()Object/FunctionObject.prototype.__defineGetter__()Object.prototype.__defineSetter__()Object.prototype.__lookupGetter__()Object.prototype.__lookupSetter__()Object.prototype.hasOwnProperty()Object.prototype.isPrototypeOf()Object.prototype.propertyIsEnumerable()Object.prototype.toLocaleString()Object.prototype.toString()Object.prototype.valueOf()| Web Proxy Viewer | New URL | Original Page |