Java String compareTo()方法与示例
字符串compareTo()方法
compareTo()是Java中的String方法，用于比较两个字符串（区分大小写）。
如果两个字符串相等-返回0，否则，根据第一个不同的字符差返回小于0或大于0的值。
语法：
int string1.compareTo(string2);
在这里，string1和string2是要比较的字符串，它返回一个整数值，该值是0，小于0或大于0。
示例
Input:
str1 = "Hello world!"
str2 = "Hello world!"
Output:
0
Input:
str1 = "Hello world!"
str2 = "HELLO WORLD!"
Output:
32Java代码使用String.compareTo()方法比较字符串
public class Main
{
public static void main(String[] args) {
String str1 = "Hello world!";
String str2 = "Hello world!";
String str3 = "HELLO WORLD!";
System.out.println("str1.compareTo(str2) = " + str1.compareTo(str2));
System.out.println("str1.compareTo(str3) = " + str1.compareTo(str3));
System.out.println("str2.compareTo(str3) = " + str2.compareTo(str3));
//检查条件
if(str1.compareTo(str2)==0){
System.out.println("str1 is equal to str2");
}
else{
System.out.println("str1 is not equal to str2");
}
if(str1.compareTo(str3)==0){
System.out.println("str1 is equal to str3");
}
else{
System.out.println("str1 is not equal to str3");
}
if(str2.compareTo(str3)==0){
System.out.println("str2 is equal to str3");
}
else{
System.out.println("str2 is not equal to str3");
}
}
}输出结果
str1.compareTo(str2) = 0 str1.compareTo(str3) = 32 str2.compareTo(str3) = 32 str1 is equal to str2 str1 is not equal to str3 str2 is not equal to str3