Top

01. 문자열 : 문자열 결합 / 템플릿 문자열

번호 기본값 속성 리턴값 
{
    const str1 = "자바스크립트";
    const str2 = "제이쿼리";

    document.querySelector(".sample01_R1").innerHTML = str1 + str2;

    const num1 = 100;
    const num2 = 200;

    document.querySelector(".sample01_R2").innerHTML = num1 + num2;

    const txt1 = "모던";
    const txt2 = "자바스크립트";
    const txt3 = "핵심";

    // 나는 모던(modern) 자바스크립트(javascript) 핵심을 배우고 싶다.

    document.querySelector(".sample01_R3").innerHTML = "나는 " + txt1 + "(modern) " + txt2 + "(javascript) " + txt3 + "을 배우고 싶다";

    const tem1 = "모던";
    const tem2 = "자바스크립트";
    const tem3 = "핵심";

    document.querySelector(".sample01_R4").innerHTML = `나는 ${tem1}(modern) ${tem2}(javascript) ${tem3}을 배우고 싶다.`;        
}

02. 문자열 속성 : length : 문자열 길이 구하기 : 반환(숫자)

번호 기본값 속성 리턴값 
{
    const str1 = "자바스크립트";
    const currentStr1 = str1.length;

    document.querySelector(".sample02_R1").innerHTML = currentStr1;


    const str2 = "javascript";
    const currentStr2 = str2.length;

    document.querySelector(".sample02_R2").innerHTML = currentStr2;  
}

03. 문자열 메서드 : toUpperCase() / toLowerCase() 문자열 대문자 변경 : 반환(문자열)

번호 기본값 속성 리턴값 
{
    const str1 = "javascript";
    const currentStr1 = str1.toUpperCase();

    document.querySelector(".sample03_R1").innerHTML = currentStr1;


    const str2 = "JAVASCRIPT";
    const currentStr2 = str2.toLowerCase();

    document.querySelector(".sample03_R2").innerHTML = currentStr2;
}

04. 문자열 메서드 : trim() : 문자열 공백 제거 : 반환(문자열)

번호 기본값 속성 리턴값 
{
    const str1 = "        ' javascript '        ";
    const currentStr1 = str1.trim();

    document.querySelector(".sample04_N1").innerHTML = 1;
    document.querySelector(".sample04_Q1").innerHTML = "'    javascript    '"
    document.querySelector(".sample04_M1").innerHTML = "trim()";
    document.querySelector(".sample04_R1").innerHTML = currentStr1;
}

05. 문자열 메서드 : indexOf() / lastIndexOf() / search() / includes() / startsWidth() / endWidth() : 문자열 검색

번호 기본값 속성 리턴값 
{
    const str = "자바스크립트(javascript) 공부"

    const text1 = str.indexOf("javascript");
    document.querySelector(".sample05_R1").innerHTML = text1;

    const text2 = str.indexOf("자바스크립트");
    document.querySelector(".sample05_R2").innerHTML = text2;

    const text3 = str.indexOf("제이쿼리");
    document.querySelector(".sample05_R3").innerHTML = text3;

    const text4 = str.indexOf('a');
    document.querySelector(".sample05_R4").innerHTML = text4;

    const text5 = str.lastIndexOf('a');
    document.querySelector(".sample05_R5").innerHTML = text5;

    const text6 = str.search('javascript');
    document.querySelector(".sample05_R6").innerHTML = text6;

    const text7 = str.search('/jquery/');
    document.querySelector(".sample05_R7").innerHTML = text7;

    const text8 = str.includes('javascript');
    document.querySelector(".sample05_R8").innerHTML = text8;

    const text9 = str.includes('jquery');
    document.querySelector(".sample05_R9").innerHTML = text9;

    const text10 = str.startsWith('자바스크립트');
    document.querySelector(".sample05_R10").innerHTML = text10;

    const text11 = str.endsWith('javascript');
    document.querySelector(".sample05_R11").innerHTML = text11;
}

06. 문자열 메서드 : charAt() : 지정한 인덱스의 문자를 추출 : 반환(문자열)

번호 기본값 속성 리턴값 
{
    const str = "자바스크립트(javascript) 공부";
    const text = str.charAt(4);

    document.querySelector(".sample06_R1").innerHTML = text;

    const text2 = str.charAt();

    document.querySelector(".sample06_R2").innerHTML = text2;   
}

07. 문자열 메서드 : slice() : 지정한 범위 내 문자열을 추출 : 반환(문자열)

번호 기본값 속성 리턴값 
{
    const str = "자바스크립트(javascript) 공부";

    const text = str.slice(1,4)
    document.querySelector(".sample07_R1").innerHTML = text;

    const text2 = str.slice(1)
    document.querySelector(".sample07_R2").innerHTML = text2;

    const text3 = str.slice(3, -1);
    document.querySelector(".sample07_R3").innerHTML = text3;

    const text4 = str.slice(7, 17);
    document.querySelector(".sample07_R4").innerHTML = text4;

    const text5 = str.slice(5, 1);
    document.querySelector(".sample07_R5").innerHTML = "실행 안됨";

    const text6 = str.substring(5, 1);
    document.querySelector(".sample07_R6").innerHTML = text6;

    const text7 = str.substr(4, 2);
    document.querySelector(".sample07_R7").innerHTML = text7;    
}

08. 문자열 메서드 : replace() : 문자열 변경 : 반환(문자열)

번호 기본값 속성 리턴값 
{
    const str = "자바스크립트(javascript) 공부";
    const text = str.replace('공부', '스터디');     

    document.querySelector(".sample08_R1").innerHTML = text;

    const str2 = "img01.jpg"
    const text2 = str2.replace('img01.jpg', 'img02.jpg');     

    document.querySelector(".sample08_R2").innerHTML = text2;

    const str3 = "010-9312-9004"
    const text3 = str3.replace('-', '');     

    document.querySelector(".sample08_R3").innerHTML = text3;

    const str4 = "010-9312-9004"
    const text4 = str4.replace(/-/g, '');  

    document.querySelector(".sample08_R4").innerHTML = text4;

    const str5 = "010-9312-9004"
    const text5 = str5.replace(/-/g, ' ');     

    document.querySelector(".sample08_R5").innerHTML = text5;    
}

09. 문자열 메서드 : split() : 문자열 반환 : 반환(문자열)

번호 기본값 속성 리턴값 
{
    const str = "자바스크립트(javascript) 공부";
    const text = str.split('');     // 한글자씩 

    document.querySelector(".sample09_R1").innerHTML = text;

    const text2 = str.split(' ');       // 한 단어씩

    document.querySelector(".sample09_R2").innerHTML = text2;

    const text3 = str.split('').join('/');      

    document.querySelector(".sample09_R3").innerHTML = text3;

    const str4 = "https://gentlemanjs.co.kr/main.html?id=1234&name=webs";
    const text4 = str4.split('&');

    document.querySelector(".sample09_R4").innerHTML = text4;

    const str5 = "https://gentlemanjs.co.kr/main.html?id=1234&name=webs";
    const text5 = str5.split(/&|\?/);

    document.querySelector(".sample09_R5").innerHTML = text5;
}

10. 문자열 메서드 : padStart() / padEnd() : 문자열 추가 반환 : (문자열)

번호 기본값 속성 리턴값 
{
    const text = num.padStart(2, '0');

    document.querySelector(".sample10_R1").innerHTML = text;

    const num2 = "456";
    const text2 = num2.padStart(6, '123');

    document.querySelector(".sample10_R2").innerHTML = text2;

    const num3 = "abc";
    const text3 = num3.padStart(3, '0');

    document.querySelector(".sample10_R3").innerHTML = text3;

    const num4 = "abc";
    const text4 = num4.padStart(6);

    document.querySelector(".sample10_R4").innerHTML = "
'" + text4 + "'
";

    const num5 = "7";
    const text5 = num5.padEnd(2, '0');

    document.querySelector(".sample10_R5").innerHTML = text5;

    const num6 = "456";
    const text6 = num6.padEnd(6, '123');

    document.querySelector(".sample10_R6").innerHTML = text6;

    const num7 = "abc";
    const text7 = num7.padEnd(3, '0');

    document.querySelector(".sample10_R7").innerHTML = text7;

    const num8 = "456";
    const text8 = num8.padEnd(6);

    document.querySelector(".sample10_R8").innerHTML = "
'" + text8 + "'
";
}

11. 문자열 메서드 : encodeURI() / encodeURIComponent() / decodeURI() / decodeURIComponent() : 문자열 인코딩/디코딩

번호 기본값 속성 리턴값 
{
    const text = "https://webstoryboy.co.kr/자바스크립트.html";
    const url = encodeURI(text);

    document.querySelector(".sample11_R1").innerHTML = url;

    const text2 = "https://webstoryboy.co.kr/자바스크립트.html";
    const url2 = encodeURIComponent(text2);

    document.querySelector(".sample11_R2").innerHTML = url2;

    const text3 = "https://webstoryboy.co.kr/%EC%9E%90%EB%B0%94%EC%8A%A4%ED%81%AC%EB%A6%BD%ED%8A%B8.html";
    const url3 = decodeURI(text3);

    document.querySelector(".sample11_R3").innerHTML = url3;

    const text4 = "https%3A%2F%2Fwebstoryboy.co.kr%2F%EC%9E%90%EB%B0%94%EC%8A%A4%ED%81%AC%EB%A6%BD%ED%8A%B8.html";
    const url4 = decodeURIComponent(text4);

    document.querySelector(".sample11_R4").innerHTML = url4;       
}