2024-06-21

Writerside/topics/String.md

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+# 문자열
+
+## String
+
+```javascript
+let str = new String("Hello");
+```
+
+```javascript
+charAt()
+charCodeAt()
+codePointAt()
+indexOf()
+lastIndexOf()
+startsWith()
+endsWith()
+includes()
+concat()
+fromCharCode()
+fromCodePoint()
+split()
+slice()
+substring()
+substr()
+match(regexp)
+replace(regexp)
+search(regexp)
+toLowerCae()
+toUpperCase()
+normalize()
+repeat()
+trim()
+```
+
+## 국제화; Intl
+
+### DateTimeFormat
+
+```javascript
+const FORMAT = new Intl.DateTimeFormat("ko-KR", {
+    year: "numeric", month: "2-digit", day: "2-digit",
+    hour: "2-digit", minute: "2-digit", second: "2-digit",
+    timeZoneName: "long"
+});
+
+let now = new Date();
+console.log(FORMAT.format(now));
+```
+
+#### 매개변수 옵션
+
+- dateStyle
+
+    - full
+    - long
+    - medium
+    - short
+- timeStyle
+
+    - full
+    - long
+    - medium
+    - short
+- timeZone
+
+  "UTC", "Asia/Seoul", …
+
+- hour12
+
+  12시간제 여부. true / false
+
+- hourCycle
+
+    - h11
+    - h12
+    - h23
+    - h24
+- weekday
+
+    - long
+    - short
+    - narrow
+- era
+
+    - long
+    - short
+    - narrow
+- year
+
+    - numeric
+    - 2-digit
+- month
+
+    - numeric
+    - 2-digit
+    - long
+    - short
+    - narrow
+- day
+
+    - numeric
+    - 2-digit
+- hour
+
+    - numeric
+    - 2-digit
+- minute
+
+    - numeric
+    - 2-digit
+- second
+
+    - numeric
+    - 2-digit
+- timeZoneName
+
+    - long
+    - short
+
+### NumberFormat
+
+```javascript
+let PRICE_FORMAT = new Intl.NumberFormat("ko-KR", {
+    style: "currency", currency: "KRW",
+    minimumFractionDigits: 2
+});
+console.log(PRICE_FORMAT.format(1000));
+```
+
+#### 매개변수 옵션
+
+- style
+
+    - decimal
+    - currency
+    - percent
+- currency
+
+  "USD", "EUR", KRW", …
+
+- currencyDisplay
+
+    - symbol
+    - code
+    - name
+- useGrouping
+
+  천 단위 구분자. true / false
+
+- minimumIntegerDigits
+
+- minimumFractionDigits
+
+- maximumFractionDigits
+
+- minimumSignificantDigits
+
+- maximumSignificantDigits