search() / match() / charAt()

search() / match() / charAt

search()

"문자열".search("검색값")
"문자열".search("정규식 표현")

 const str1 = "javascript reference" 
    const currentStr1 = str1.search("javascript");     // 0
    const currentStr2 = str1.search("reference");      // 11
    const currentStr3 = str1.search("j");              // 0
    const currentStr4 = str1.search("a");              // 1
    const currentStr5 = str1.search("v");              // 2
    const currentStr6 = str1.search("jquery");         //-1
    const currentStr7 = str1.search("b");              //-1 데이터값이 없으면 -1
    const currentStr8 = str1.search(/[a-z]/g);         // 0    

search() 메서드는 문자열(정규식)을 검색하고 위치값(숫자)를 반환합니다.

match()

"문자열".search("검색값")
"문자열".search("정규식 표현")

  const str1 = "javascript reference" 
    const currentStr1 = str1.match("javascript");        //[javascript]
    const currentStr2 = str1.match("reference");         //[reference]
    const currentStr3 = str1.match("r");                 //[r]
    const currentStr4 = str1.match(/reference/g);        //['reference']
    const currentStr5 = str1.match(/Reference/g);        //null
    const currentStr6 = str1.match(/Reference/i);        //[reference]
    const currentStr7 = str1.match(/r/g);                //['r', 'r', 'r']
    const currentStr8 = str1.match(/e/g);                //['e', 'e', 'e', 'e']

indexOf와 비슷하지만 match는 정규식표현도 지원하고 배열로 반환한다.

charAt()

"문자열".charAt(숫자);

 const str1 = "javascript reference" 
    const currentStr1 = str1.charAt();        //[j]
    const currentStr2 = str1.charAt("0");        //[j]
    const currentStr3 = str1.charAt("1");        //[a]
    const currentStr4 = str1.charAt("2");        //[v]

charAt는 불러온 문자열에서 원하는 위치의 문자열을 반환합니다.