Common operations collation of the String class

A. String class character and string manipulation:

• public char charAt (int index) finds the specified character according to the subscript

• Public char[] ToCharArray () returns all string contents as a character array

• public string (char[] value) converts all character arrays into string construction methods

• public string (char[] Value,int offset,int count) changes the character array of the specified range into a string construction method

Two. String-like byte-action

• Public Byte[]getbytes () turns a string into a byte array

• public string (byte[]bytes) converts a byte array into a string construction method

• public string (byte[]bytes,int offset,int length) converts the byte array of the specified range into a string construction method

• Public srring (byte[]bytes,string charsetname) constructs a new String construction method by decoding the specified byte array with the specified charset

Three. The string class determines whether to start or end with the specified content

• public boolean startsWith (String prefix) starts at the first position to determine whether to start with the specified content

• public boolean startsWith (String prefix,int toffset) starts at the specified position to determine whether to start with the specified content

• public boolean endsWith (String suffix) determines whether to end with the specified content

Four. Substitution of the String class:

• Public String replace (char OldChar, char Newchar) replaces the specified character

• public string replace (charsequence target,charsequence replacement) replaces the specified string

• public string ReplaceAll (srring regex,string replacement) replaces the specified string regex represents a regular expression

• public string Replacefirst (srring regex,string replacement) replaces the first string that satisfies a condition

Five. String interception operations for string classes

• Public String substring (int beginindex) is truncated to the end starting at the specified position

• public string substring (int beginindex,int endIndex) intercepts a string of a specified range note: Include the starting position but not the end position

Six. String splitting operation of String class

• Public string[] Split (string regex) is split according to the specified string

• Public string[] Split (string regex,int limit) splits the string and specifies the number of splits

Seven. String lookup operation for String class

• Public Boolean contains (string s) returns whether a string exists

• public int indexOf (int ch) finds from the beginning whether the specified character exists, char->int, if present, returns the position if no return-1 is present.

• The public int indexOf (int ch,int fromIndex) finds the specified character from the specified location, char->int if it exists, returns the position if there is no return-1

• public int indexOf (string str) finds from the beginning whether the specified string exists, returns a position if it exists, and returns 1 if it does not exist.

• The public int indexOf (string str,int fromIndex) finds the specified string from the specified location, returns a position if it exists, and returns 1 if it does not exist.

• Note: The above position is the first occurrence of the position

• public int lastIndexOf (int ch) looks up from the last forward of the string, whether the specified character exists, returns the position if it exists, and returns 1 if it does not exist.

• public int lastIndexOf (int ch,int fromIndex) looks forward from the specified end of the string, whether the specified character exists, returns a position if it exists, and returns 1 if it does not exist.

Eight. Other methods of operation of the String class

• public Boolean isEmpty () determines whether it is empty, only the content is empty "".

• public int Length () Gets the lengths of the strings

• Public String tolowercase () turns lowercase

• Public srring toUpperCase () to uppercase

• Public String trim () removes the opening and closing spaces, and the space in the middle does not go

• public string concat (string str) string connection operation

Common operations collation of the String class