Java 字串比較方法。
Java String 類提供了不同的比較方法,包括
compareTo() 方法
此方法按字典順序比較兩個字串。此方法返回: 如果當前字串物件按字典順序在引數字串前面,則返回值為負整數。 如果當前字串物件按字典順序在引數後面,則返回值為正整數。 如果字串相等,則返回值為 true。
示例
import java.lang.*;
public class StringDemo {
public static void main(String[] args) {
String str1 = "tutorials", str2 = "point";
// comparing str1 and str2
int retval = str1.compareTo(str2);
// prints the return value of the comparison
if (retval < 0) {
System.out.println("str1 is greater than str2");
}
else if (retval == 0) {
System.out.println("str1 is equal to str2");
} else {
System.out.println("str1 is less than str2");
}
}
}輸出
str1 is less than str2
compareToIgnoreCase() 方法
此方法與 compareTo() 方法相同,它按字典順序比較兩個字串,忽略大小寫差異。
示例
import java.lang.*;
public class StringDemo {
public static void main(String[] args) {
String str1 = "tutorials", str2 = "TUTORIALS";
// comparing str1 and str2 with case ignored
int retval = str1.compareToIgnoreCase(str2);
// prints the return value of the comparison
if (retval > 0) {
System.out.println("str1 is greater than str2");
}
else if (retval == 0) {
System.out.println("str1 is equal to str2");
} else {
System.out.println("str1 is less than str2");
}
}
}輸出
str1 is equal to str2
equals() 方法
此方法將該字串與指定物件進行比較。當且僅當引數不是 null 並且它表示與此物件相同字元序列的字串物件時,結果才為 true。
示例
import java.lang.*;
public class StringDemo {
public static void main(String[] args) {
String str1 = "sachin tendulkar";
String str2 = "amrood admin";
String str3 = "amrood admin";
// checking for equality
boolean retval1 = str2.equals(str1);
boolean retval2 = str2.equals(str3);
// prints the return value
System.out.println("str2 is equal to str1 = " + retval1);
System.out.println("str2 is equal to str3 = " + retval2);
}
}輸出
str2 is equal to str1 = false str2 is equal to str3 = true
equalsIgnoreCase() 方法
此方法與 ignoreCase() 方法相同,但如果兩個字串長度相同,並且這兩個字串中的對應字元在忽略大小寫的情況下相等,則認為這兩個字串是相等的。
示例
import java.lang.*;
public class StringDemo {
public static void main(String[] args) {
String str1 = "sachin tendulkar";
String str2 = "amrood admin";
String str3 = "AMROOD ADMIN";
// checking for equality with case ignored
boolean retval1 = str2.equalsIgnoreCase(str1);
boolean retval2 = str2.equalsIgnoreCase(str3);
// prints the return value
System.out.println("str2 is equal to str1 = " + retval1);
System.out.println("str2 is equal to str3 = " + retval2);
}
}輸出
str2 is equal to str1 = false str2 is equal to str3 = true
廣告
資料結構
網路
RDBMS
作業系統
Java
iOS
HTML
CSS
Android
Python
C 程式設計
C++
C#
MongoDB
MySQL
Javascript
PHP