revision:
charAt() : returns the character at the specified index.
syntax: let str = "Hello"; console.log(str.charAt(1)); // 'e'
charCodeAt() : returns a number indicating the Unicode value of the character at the given index.
syntax: let str = "A"; console.log(str.charCodeAt(0)); // 65
concat() : combines the text of two strings and returns a new string.
syntax: let str1 = "Hello"; let str2 = "World"; console.log(str1.concat(" ", str2)); // "Hello World"
indexOf() : returns the index within the calling String object of the first occurrence of the specified value, or -1 if not found.
syntax: let str = "Hello World"; console.log(str.indexOf("o")); // 4
lastIndexOf() : returns the index within the calling String object of the last occurrence of the specified value, or -1 if not found.
syntax: let str = "Hello World"; console.log(str.lastIndexOf("o")); // 7
localeCompare() : returns a number indicating whether a reference string comes before or after or is the same as the given string in sort order.
syntax: console.log("a".localeCompare("b")); // -1 console.log("b".localeCompare("a")); // 1 console.log("a".localeCompare("a")); // 0
length() : returns the length of the string.
syntax: let str = "Hello"; console.log(str.length); // 5
match() : used to match a regular expression against a string.
syntax: let str = "The rain in Spain falls mainly in the plain"; let matches = str.match(/in/g); console.log(matches); // ["in", "in", "in", "in"]
replace() : used to find a match between a regular expression and a string, and to replace the matched substring with a new substring.
syntax: let str = "Hello World"; console.log(str.replace("World", "Universe")); // "Hello Universe"
search() : executes the search for a match between a regular expression and a specified string.
syntax:
slice() : extracts a section of a string and returns a new string.
syntax: let str = "Hello World"; console.log(str.slice(0, 5)); // "Hello"
split() : splits a String object into an array of strings by separating the string into substrings.
syntax: let str = "apple,banana,orange"; console.log(str.split(",")); // ["apple", "banana", "orange"]
substr() : returns the characters in a string beginning at the specified location through the specified number of characters.
syntax: let str = "Hello World"; console.log(str.substr(6, 5)); // "World"
substring() : returns the characters in a string between two indexes into the string.
syntax: let str = "Hello World"; console.log(str.substring(0, 5)); // "Hello"
toLocaleLowerCase() : the characters within a string are converted to lower case while respecting the current locale.
syntax: const dotted = "İstanbul"; console.log(`EN-US: ${dotted.toLocaleLowerCase("en-US")}`); // Expected output: "i̇stanbul" console.log(`TR: ${dotted.toLocaleLowerCase("tr")}`); // Expected output: "istanbul"
toLocaleUpperCase() : the characters within a string are converted to upper case while respecting the current locale.
syntax: const city = "istanbul"; console.log(city.toLocaleUpperCase("en-US")); // Expected output: "ISTANBUL" console.log(city.toLocaleUpperCase("TR")); // Expected output: "İSTANBUL"
toLowerCase() : returns the calling string value converted to lower case.
syntax: let text = "Hello World!"; let result = text.toLowerCase(); console.log(result); // "hello world!"
toString() : returns a string representing the specified object.
syntax: let text = "Hello World!"; let result = text.toString(); console.log(result); // "Hello World!"
toUpperCase() : returns the calling string value converted to uppercase.
syntax: let str = "hello"; console.log(str.toUpperCase()); // "HELLO"
valueOf() : returns the primitive value of the specified object.
syntax: let num = new Number(12); console.log(num); // Output: [Number: 12] console.log(num.valueOf()); // Output: 12
<div> <a id="string1"></a><br> <a id="string2"></a><br><br> <a id="string3"></a><br> <a id="string4"></a><br> <a id="string5"></a><br> <a id="string6"></a><br> <a id="string7"></a><br> <a id="string8"></a><br> <a id="string9"></a><br> <a id="string10"></a><br> <a id="string11"></a><br> <a id="string12"></a><br> <a id="string13"></a><br> <a id="string14"></a><br> <a id="string15"></a><br> <a id="string16"></a><br> <a id="string17"></a><br> <a id="string18"></a><br> </div> <script> var str1 = "Lorem Ipsum is simply dummy text of the printing and typesetting industry" var str2 = str1.toUpperCase() document.getElementById("string1").innerHTML = "first string : " + str1; document.getElementById("string2").innerHTML = "second string : " + str2; var newStr = str1.toUpperCase() document.getElementById("string3").innerHTML = "toUpperCase : " + newStr; var newStr1 = str2.toLowerCase() document.getElementById("string4").innerHTML = "toLowerCase : " + newStr1; var newStr2 = str1.slice(-8, -1) document.getElementById("string5").innerHTML = "slice : " + newStr2; var newStr3 = str1.substring(1, 6) document.getElementById("string6").innerHTML = "substring : " + newStr3; var newStr4 = str1.substr(8, 15) document.getElementById("string7").innerHTML = "substr : " + newStr4; var newStr5 = str1.replace("is", "are") document.getElementById("string8").innerHTML = "replace : " + newStr5; var str3 = "Java"; var str4 = "Script"; var newStr6 = str3.concat(str4) document.getElementById("string9").innerHTML = "concat : " + newStr6; var str5 = " JavaScript "; var newStr7 = str5.trim() document.getElementById("string10").innerHTML = "trim : " + newStr7; var str6 = "JavaScript, is, useful"; var newStr7 = str6.split(",") document.getElementById("string11").innerHTML = "split : " + newStr7[0]; document.getElementById("string12").innerHTML = "split : " + newStr7[2]; var str7 = "JavaScript is useful"; var newStr8 = str7.charCodeAt(str7[1]); document.getElementById("string13").innerHTML = "charCodeAt : " + newStr8; var newStr9 = str7.charAt(1); document.getElementById("string14").innerHTML = "charAt : " + newStr9; var str9 = "15" var newStr10 = str9.padStart(4, "3"); document.getElementById("string15").innerHTML = "padStart : " + newStr10; var newStr11 = str9.padEnd(4, "3"); document.getElementById("string16").innerHTML = "padEnd : " + newStr11; var newStr12 = str6.length; document.getElementById("string17").innerHTML = "length : " + newStr12; </script>