javastring类方法表格(javastring类常用方法)-捕鱼10元起上10元下

introduction

java is one of the most popular programming languages in the world. the language is widely used for developing desktop applications, web-based applications, and mobile applications. java is an object-oriented language that provides a lot of classes and methods to make programming easier. one of these classes is the string class. the string class is used to create and manipulate strings in java. this class contains a lot of methods that can be used to work with strings. in this article, we will explore the java string class methods by breaking them down into different categories.

methods to create a string

the first category of string class methods is the methods that are used to create a string. there are several methods provided by the string class to create a new string. these methods include:

• string(): this method creates an empty string.
• string(char[] value): this method creates a new string by copying the characters of the given character array.
• string(char[] value, int offset, int count): this method creates a new string by copying the specified range of characters from the given character array.
• string(byte[] bytes): this method creates a new string by decoding the specified array of bytes using the platform's default charset.

methods to manipulate a string

the second category of string class methods is the methods that are used to manipulate a string. these methods are used to modify or extract some parts of the string. these methods include:

• concat(string str): this method concatenates the specified string to the end of the current string.
• charat(int index): this method returns the character at the specified index.
• length(): this method returns the length of the string.
• substring(int beginindex): this method returns a new string that is a substring of the current string, starting from the specified index.
• substring(int beginindex, int endindex): this method returns a new string that is a substring of the current string, starting from the specified begin index and ending at the specified end index.
• replace(char oldchar, char newchar): this method replaces all occurrences of the specified character in the string with the new character.
• touppercase(): this method returns a new string in uppercase letters.
• tolowercase(): this method returns a new string in lowercase letters.

methods to compare strings

the third category of string class methods is the methods that are used to compare strings. these methods are used to check whether two strings are equal, or one string is greater or less than the other string. these methods include:

• equals(object anobject): this method checks whether the current string is equal to the specified object.
• compareto(string anotherstring): this method compares the current string with the specified string lexicographically.
• startswith(string prefix): this method checks whether the current string starts with the specified prefix.
• endswith(string suffix): this method checks whether the current string ends with the specified suffix.

in conclusion, the string class is a very important class in java that is used to create and manipulate strings. this class provides a lot of methods that can be used to work with strings. the methods can be categorized into methods to create a string, methods to manipulate a string, and methods to compare strings. these methods are very useful for developers who are working with strings in their java applications.