Liaoche JS Tutorial Learn to record---string

1. Since multiline strings are more \n cumbersome to write, the newest ES6 standard adds a multi-line string representation, using ' ... '`这是一个

多行字符串`;

2.字符串常见的操作如下：

// 13

要获取字符串某个指定位置的字符，使用类似Array的下标操作，索引号从0开始：

s[12]; // ‘!‘s[13]; // undefined 超出范围的索引不会报错，但一律返回undefined

3. It is important to note that the string is immutable, and there is no error if you assign a value to an index of the string, but it does not have any effect:

var s = ‘Test‘;s[0] = ‘X‘;alert(s); // s仍然为‘Test‘

4.JavaScript provides some common methods for strings, note that calling these methods does not alter the contents of the original string, but instead returns a new string:

toUpperCase (): Turns a string into uppercase toLowerCase: turns a string all lowercase indexOf: searches for the starting position where the specified string appears, and cannot find the return to-1SUBSTRING: Returns the substring of the specified index interval:

var s = ‘hello, world‘s.substring(0, 5); // 从索引0开始到5（不包括5），返回‘hello‘s.substring(7); // 从索引7开始到结束，返回‘world‘

Liaoche JS Tutorial Learn to record---string