劉任昌w3schools學Java,整數int,字串String,迴圈for loop,Character.toString將字碼轉字元

Java,整數int,字串String,迴圈for loop
/*劉任昌2022/10/21學習迴圈for loop利用挪威w3schools*/
public class Main {                 /*類別名稱Main存檔的檔名必須Main.java*/
  public static void main(String[] args) {
    int i, j, k=12;                 /*宣告整數integer, i*/
    String a="第", b="列: ";        /*宣告整數字串 */
    for (i = k; i > 0; i--) {
      System.out.print( a + i + b); /*+用於字串變數,串接,相當於excel的*/
      for (j=1; j<=i; j++)
        System.out.print(j+" ");   /*語法syntax錯誤,邏輯logic錯誤*/
      System.out.println();        /*println=print line印完到下一列*/
    }  
  }
}

w3schools學習Java截圖

Character.toString將字碼轉字元
/*劉任昌2022/10/21學習迴圈for loop利用挪威w3schools*/
public class Main {   /*類別名稱Main存檔的檔名必須Main.java*/
  public static void main(String[] args) {
    int i, j, k=12;                 /*宣告整數integer, i*/
    String a="第", b="列: ";        /*宣告整數字串 */
    for (i = k; i > 0; i--) {
      System.out.print( a + i + b);/*+用於字串變數,串接,相當於excel的&*/
      for (j=1; j<=i; j++)
        System.out.print(j+" ");   /*語法syntax錯誤,邏輯logic錯誤*/
      System.out.println();        /*println=print line印完到下一列*/
    }                              /*捲括號curly bracket{ }*/  
    a = " 字碼是字元 ";
    System.out.println(48 + a + Character.toString(48));
    System.out.println(65 + a + Character.toString(65));
    System.out.println(97 + a + Character.toString(97));
    System.out.println(122 + a + Character.toString(122));
    System.out.println("傳統ascii只到127,字碼系統再擴展到所有文字unicode系統");
    for ( i = 40845; i < 40860; i++){
       b = Character.toString(i);
       System.out.println(i + a + b);
    }
  }
}

Character.toString將字碼轉字元

字元轉字碼Integer.valueOf