let message = "Hello, world!"; console.log(message.length); // Output: 13
let greeting = "Hello"; let name = "Alice"; let fullGreeting = greeting.concat(", ", name, "!"); console.log(fullGreeting); // Output: "Hello, Alice!"
let message = "JavaScript"; console.log(message.charAt(0)); // Output: "J" console.log(message.charAt(5)); // Output: "S"
let sentence = "The quick brown fox jumps over the lazy dog."; console.log(sentence.indexOf("quick")); // Output: 4 console.log(sentence.indexOf("dog")); // Output: 37 console.log(sentence.indexOf("lion")); // Output: -1 (not found)
let quote = "To be, or not to be, that is the question."; console.log(quote.lastIndexOf("be")); // Output: 23 console.log(quote.lastIndexOf("the")); // Output: 33
let fruit = "apple, banana, cherry"; console.log(fruit.slice(0, 5)); // Output: "apple" console.log(fruit.slice(7, 13)); // Output: "banana" console.log(fruit.slice(15)); // Output: "cherry"
let text = "Hello, world!"; console.log(text.substring(0, 5)); // Output: "Hello" console.log(text.substring(7, 12)); // Output: "world"
let message = "The quick brown fox jumps."; console.log(message.substr(4, 5)); // Output: "quick" console.log(message.substr(10)); // Output: "brown fox jumps."
let text = "JAVASCRIPT IS AWESOME!"; console.log(text.toLowerCase()); // Output: "javascript is awesome!"
let text = "hello, world!"; console.log(text.toUpperCase()); // Output: "HELLO, WORLD!"
let greeting = " Hello, world! "; console.log(greeting.trim()); // Output: "Hello, world!"
let text = "I like cats. Cats are fluffy."; console.log(text.replace("cats", "dogs")); // Output: "I like dogs. Cats are fluffy." console.log(text.replace(/cats/i, "dogs")); // Output: "I like dogs. Cats are fluffy." (case-insensitive)
let csv = "apple,banana,cherry"; let fruits = csv.split(","); console.log(fruits); // Output: ["apple", "banana", "cherry"]
let message = "The quick brown fox jumps over the lazy dog."; console.log(message.includes("quick")); // Output: true console.log(message.includes("tiger")); // Output: false
let greeting = "Hello, world!"; console.log(greeting.startsWith("Hello")); // Output: true console.log(greeting.startsWith("world")); // Output: false
let filename = "myfile.pdf"; console.log(filename.endsWith(".pdf")); // Output: true console.log(filename.endsWith(".txt")); // Output: false
let text = "The quick brown fox jumps."; let pattern = /quick/; console.log(text.match(pattern)); // Output: ["quick"]
let text = "The quick brown fox jumps."; let pattern = /brown/; console.log(text.search(pattern)); // Output: 10
let message = "Hello "; console.log(message.repeat(3)); // Output: "Hello Hello Hello "
let greeting = " Hello, world! "; console.log(greeting.trimStart()); // Output: "Hello, world! "
let greeting = " Hello, world! "; console.log(greeting.trimEnd()); // Output: " Hello, world!"
let number = "42"; console.log(number.padStart(4, "0")); // Output: "0042"
padEnd():
let word = "JavaScript";
console.log(word.padEnd(15, ".")); // Output: "JavaScript....."
splice():
let str = "Hello, world!"; let result = str.splice(7, 5, "everyone"); console.log(result); // Output: "world" console.log(str); // Output: "Hello, everyone!"
let num = 42; console.log(num.toString()); // Output: "42"
let str = "JavaScript"; console.log(str.valueOf()); // Output: "JavaScript"
let message = "Hello"; console.log(message.charCodeAt(0)); // Output: 72 console.log(message.charCodeAt(4)); // Output: 111
let emoji = "?"; console.log(emoji.codePointAt(0)); // Output: 128512
normalkan():
let str1 = "café"; let str2 = "cafe\u0301"; console.log(str1.normalize() === str2.normalize()); // Output: true
Ini merangkumi pelbagai tugas manipulasi rentetan dalam JavaScript, daripada operasi asas seperti mendapatkan panjang atau rentetan gabungan kepada teknik yang lebih maju seperti padanan corak dan penormalan Unikod.
Atas ialah kandungan terperinci senarai kaedah rentetan JavaScript yang paling biasa. Untuk maklumat lanjut, sila ikut artikel berkaitan lain di laman web China PHP!