java8錯誤找不到符號當我使用comparetoIgnoreCase和Upper/UnderCase

Question

我想比較string_1到string_2，看看它是否相等，而我試圖使一個單獨的字符串被完全大寫或under-套管。

import java.util.Scanner; 
 
public class StringMethods 
 
    { 
 
    public static void main (String [] args) 
 
     { 
 
     Scanner s=new Scanner (System.in); 
 
     String string_1= s.next(); 
 
     String string_2= s.next(); 
 
     System.out.println ("a) Determine the length of string_1: " +string_1.length()+ "/t b) Determine the length of string_2: " +string_2.length()+"/tc) Concatenate both strings: " +string_1.concat(string_2)+"/td) Check if the two strings have same set of characters with regard to case: "); 
 
     if (string_1.equaltoIgnoreCase(string_2)) 
 
     { 
 
     System.out.print ("equal."); 
 
     } 
 
     if ((string_1.comparetoIgnoreCase(string_2)>0)||(string_1.comparetoIgnoreCase(string_2)<0)) 
 
     { 
 
     System.out.print ("They are not equal."); 
 
     } 
 
     System.out.println ("e) Convert string_1 to upper case: " +string_1.toUpperCase()+"/tf) Convert string_2 to lower case: " +string_2.toUnderCase()+"/tg) Extract a valid sub-string of multiple characters from string_1: " +string_1.substring(0,string_1.length)); 
 
     }}

Answer 1

你有很多拼寫和標點錯誤的整個代碼。我強烈建議使用像IntelliJ這樣的IDE來防止這種情況。我繼續前進並修正了錯字，但看起來您需要按照程序當前運行的方式進行一些工作。例如，該程序在用戶甚至知道要輸入什麼之前要求輸入。

import java.util.Scanner; 

public class Test { 
    public static void main(String[] args) { 
     Scanner s = new Scanner(System.in); 
     String string_1 = s.next(); 
     String string_2 = s.next(); 
     System.out.println("a) Determine the length of string_1: " + 
string_1.length() + "/t b) Determine the length of " + 
      "string_2: " + string_2.length() + "/tc) Concatenate both 
strings: " + string_1.concat(string_2) + "/td) " + 
      "Check if the two strings have same set of characters 
with regard to case: "); 
    if (string_1.equalsIgnoreCase(string_2)) { 
     System.out.print("equal.");`enter code here` 
    } 
    if ((string_1.compareToIgnoreCase(string_2) > 0) || 
(string_1.compareToIgnoreCase(string_2) < 0)) { 
     System.out.print("They are not equal."); 
    } 
     System.out.println("e) Convert string_1 to upper case: " + 
string_1.toUpperCase() + "/tf) Convert string_2 to " + 
      "lower case: " + string_2.toLowerCase() + "/tg) Extract a 
valid sub-string of multiple characters from string_1: " + 
      string_1.substring(0, string_1.length())); 
    } 
}