자바 형변환 정리

String -> 숫자형 (int, double, float, long, short)

String s = "123";
int i = Integer.parseInt(s);
int i2 = Integer.valueOf(s);
double d = Double.parseDouble(s);

String -> char

String s = "abc";
char c = s.charAt(0);

String -> char 배열

String s = "abc";
char[] cArr = s.toCharArray();

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숫자형 (int, double, float, long, short) -> String

int i = 123;
String s1 = String.valueOf(i);
String s2 = Integer.toString(i);
String s3 = i + "";

int -> char

int i = 1;

char c1 = (char) (i + '0');

int radix = 10; //10진수
char c2 = Character.forDigit(i , radix);

char c3 = Integer.toString(i).charAt(0);

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char -> String

char c = 'A';
String s = Character.toString(c);

char 배열 -> String

char c[] = {'a','b'};
String s = String.valueOf(c);

char -> int

char c = '1';

int i1 = c - '0';

int i2 = Character.getNumericValue(c);