在Java中实现“自动递增”字母表 - 是否有可能从A到Z而不使用第三方库?
在Java中实现“自动递增”字母表 - 是否有可能从A到Z而不使用第三方库?
是的,你可以像这样做:
for (char alphabet = 'A'; alphabet <= 'Z'; alphabet++) {
System.out.println(alphabet);
}
使用类型转换也是可能的:
for (int i = 65; i <= 90; i++) {
System.out.println((char)i);
}
for (int i = 0; i < 26; i++)
{
char upper = (char) ('A' + i);
char lower = (char) ('a' + i);
...
}
for (char c = 'A'; c <= 'Z'; c++) {
...
}
for( int i = 'a'; i < 'z'; i++ )
System.out.println((char)i); // Cast int to char
Java 8强制解决方案:
IntStream.rangeClosed('A', 'Z')
.mapToObj(c -> "" + (char) c)
.forEach(System.out::println);
class Alphabet implements Iterable<String>{
private char start;
private char end;
public Alphabet(char start, char end) {
this.start=start;
this.end=end;
}
@Override
public Iterator<String> iterator() {
return new AlphabetIterator(start, end);
}
class AlphabetIterator implements Iterator<String>{
private String current;
private String end;
private AlphabetIterator(char start, char end) {
this.current=String.valueOf(--start);
this.end=String.valueOf(end);
}
@Override
public boolean hasNext() {
return (current.charAt(0) < end.charAt(0));
}
@Override
public String next() {
char nextChar = current.charAt(0);
return this.current=String.valueOf(++nextChar);
}
}
public static void main (String[] arg){
for (String str:new Alphabet('B', 'Y')){
System.out.print(str+" ");
}
}
}
for (char c = 'a'; c <= 'z'; c++)
//whatever
for (char alphabet = 'a'; alphabet <= 'z'; alphabet++) {
System.out.println(alphabet);
}
for(int i = 0; i < 26; i++)
{
System.out.println((char)('A' + i) + ":" + ('A' + i) + " : " + (char)('a' + i) + ":" + ('z' + i));
}