Java String startsWith（）方法与示例

字符串startsWith()方法 (String startsWith() Method)

startsWith() method is a String class method, it is used to check whether a given string starts with specific character sequences or not.

startsWith()方法是一个String类方法，用于检查给定的字符串是否以特定的字符序列开头。

If a string starts with given character sequences – startsWith() method returns true, if a string does not start with the given character sequences – startsWith() method returns false.

如果字符串以给定的字符序列开头-startsWith()方法将返回true ，如果字符串不是以给定的字符序列开头-则startsWith()方法将返回false 。

Syntax:

句法：

    boolean String_object.startsWith(character_sequence);

Here,

这里，

• String_object is the main string in which we have to check whether it starts with given character_sequence or not.

  String_object是主要字符串，我们必须在其中检查是否以给定的character_sequence开头。

• character_sequence is the set of character to be checked.

  character_sequence是要检查的字符集。

Example:

例：

    Input:
    str = "Hello world!"
    Function call:
    str.startsWith("Hello");
    Output:
    true

    Input:
    str = "IncludeHelp"
    Function call:
    str.startsWith("inc");
    Output:
    false

Code:

码：

public class Main
{
    public static void main(String[] args) {
        String str1 = "Hello world!";
        String str2 = "IncludeHelp";
        
        System.out.println(str1.startsWith("Hello"));
        System.out.println(str1.startsWith("inc"));
        
        //checking through the conditions
        if(str1.startsWith("Hello")){
            System.out.println(str1 + " starts with Hello" );
        }
        else{
            System.out.println(str1 + " does not start with Hello" );
        }
        //note: method is case sensitive
        if(str2.startsWith("inc")){
            System.out.println(str2 + " starts with inc" );
        }
        else{
            System.out.println(str2 + " does not start with inc" );
        }        
    }
}

Output

输出量

true
false
Hello world! starts with Hello
IncludeHelp does not start with inc

翻译自: https://www.includehelp.com/java/string-startsWith-method-with-example.aspx