1. String object
A String object is used to process text (string).
2. Constructor function
new String(value)//Constructor
function String(value)//Conversion function
3. Attributes
length number of characters in this string
var str = new String("abcdefg");
(); //Output 7
4. Method
1. chatAt() takes out a character at the specified position in a string.
var str = new String("abcdefg");
((1)); //Output b
2. chatCodeAt() returns the encoding of the characters at the specified position in a string.
var str = new String("abcdefg");
((1)); //Output 98
3. concat() concatenates one or more values into a string.
var str = new String("abcdefg");
var str1 = "hijk";
((str1)); //Output abcdefghijk
4. indexOf() finds the location of a character or string in the specified string. If no searches are found, return -1
Syntax: indexOf(str) str: substring or character
indexOf(str,start)str: substring or character. start: Specify the start location of the search
var str = new String("abccba");
(('b')); //Output 1 (("bc")); //Output 1
Use this method to implement the Contains effect and determine whether a string contains another string:
<script type="text/javascript">
= function () {
var str1 = "Liu Bei";
var str2 = "Liu Bei is a great man!";
alert((str1)); //Output 0 appears if ((str1) > -1) {
alert("Include!");
}
else {
alert("Not included!");
}
}
</script>
5. LastIndexOf() looks for the position of a character or string backwards (inverted) in the specified string. If no searches are found, return -1
Syntax: lastIndexOf(str) str: substring or character
lastIndexOf(str,start)str: a substring or character. start: Specify the start location of the search
var str = new String("abccba");
(('b')); //Output 4
6. localeCompare() compares strings using locally defined order.
var str = "abccba";
(("bc"));//Output -1
7. match() uses regular expressions to perform pattern matching.
8. replace() uses regular expressions to perform search and replace operations.
var str = "abccba";
(("b","-"));//Output a-ccba
9. Search() finds a string that matches a regular expression in a string.
var str = "abccba";
(("b")); //Output 1
10. slice() returns a slice or string of the string. If the parameter is a negative number, it means the number from behind to front. Do not change the original string.
var str = "abcdefg";
((2) + "<br/>"); //Output cdefg (str); //OutputabcdefgYou can see that the original string has not changed。
11. split() is broken with the specified delimiter string or regular expression, and returns the string array.
var str = "abcdefg";
var arr = ("d");
(()); //Outputabc,efg
12. substr() extracts a substring of a string, a variant of substring(). Deprecated.
13. substring() Extracts a substring of a string.
Syntax: substring(start,end) starts from start and ends, including start but not end. Do not change the original string.
var str = "12345678";
((1,4));//Output 234
14. toLowerCase() returns a lowercase copy of the specified string.
var str = "abcDEF";
(()); //Output abcdef
15. toString() returns the original string value.
var str = "abcDEF";
(()); //Output abcDEF
16. toUpperCase() returns a capital copy of the specified string.
var str = "abcDEF";
(()); //Output ABCDEF
17. trim() returns a copy of the specified string that is blank before and after removal.
var str = " abcDEF ";
("11" + () + "11" + "<br/>"); //Output 11abcDEF11 ("11" + str + "11"); //Output 11 abcDEF 11
18. valueOf() returns the original string value.
var str = "abcDEF";
(()); //Output abcDEF
The above is all the content of this article. I hope it will be helpful to everyone. Thank you for your support!