Summary of common methods of string

List of articles

One 、 Construction method

Two 、 Static methods

3、 ... and 、 Other methods

One 、 Construction method

  There are two kinds of construction methods in the string, namely, non parametric construction method and parametric construction method

1、String s1=" China ";

2、String s2=new String（“ China ”）;// Create an object , Point to string constant object .

3、String s3=new String（char Array ）;// take char Each character stored in the array is connected to form a string

4、String s3=new String（char Array , Start subscript , length ）;// take char From the starting position of the storage in the array lenth Characters form a string

5、String s3=new String（byte Array ）;// take byte The numbers stored in the array are spliced into a string

6、String s3=new String（byte Array , Start subscript , length ）;// take byte The number stored in the array is from the starting subscript to the starting subscript + length , Concatenate into strings .

 

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Two 、 Static methods

Common static methods

1. public static String copyValueOf(char[] data)

   Returns the string representing the character sequence in the specified array

2. public static String copyValueOf(char[] data, int offset, int count)

   Returns the string representing the character sequence in the specified array

     3.public static Stirng format(String format, Object... args)

        Format output string

     4.public static Stirng format(Locale locale, String format, Object... args)

         Use the specified language environment , Format output string
     5.public static String join(CharSequence delimiter, CharSequence... elements) 

        Pass in parameters to replace placeholders , Generate a new string

      

3、 ... and 、 Other methods

        1.  public int indexOf(String str） Find the position of the incoming string in the current string backwards from the starting position , There is a return subscript , There is no return -1

        2.public int lastIndexOf(String str)  Find the position of the incoming string in the current string from the end position forward , There is a return subscript , There is no return -1

        3. public boolean contains(CharSequence s) Finding the passed in parameter backwards from the start position can make the character type or string type , Return to one boolean Type value , Found return true, Otherwise return to false

        4.public String substring(int beginIndex, int endIndex) from beginIndex Start to endIndex end , Intercept the current string , And return a new string

        5.public String trim()   Remove strings " Both ends " Space wrap （ Blank character , And return a new string

        6. public String replace(char oldChar, char newChar) String replaces the old string , And return a new string

        7.public String[] split(String regex) As specified regex（ Regular expressions ） Split the string , Returns a new string array

        8.public byte[] getBytes()  Get the encoded value of the string , The default is Unicode code