What are the common methods of JavaScript built-in objects?
Commonly used methods of built-in objects: concat(), join(), pop(), shift(), slice(), splice(), push(), sort(), reverse(), toLocaleString( ), escape(), eval(), etc.
The operating environment of this tutorial: windows7 system, javascript version 1.8.5, Dell G3 computer.
Commonly used built-in objects in JS: Array object, Date object, string object, Global object
Commonly used methods in Array object:
concat( ) Indicates merging several arrays into one array
join() Set the separator to connect the array elements into a string
pop() Remove the last element of the array
shift() Remove the first element of the array
slice(start, end) Return to the array A section of
splice() can be used to delete, insert, or replace
push() to the array Add a new element and return the latest length
sort() Sort the array
-
reverse() Reverse the order of the array
toLocaleString() Convert the array to a local string
Commonly used methods of Global objects:
Global properties and functions can be used All built-in JavaScript objects
escape() Encoding string
eval() Parse the string into JavaScript code and execute it
-
isNaN()
##parseFloat() Parse a string and return a floating point number - number() Convert the value of the object to a number
- string() Convert the value of the object to a string
- Common methods of String object
-
charAt() Return the specified index The character at the position
- lastIndexOf() Search the string before to see if it contains the specified string
##concat() Concatenate two or more strings
match() Use The regular expression pattern performs a search on a string and returns the result containing the search result
replace() Replaces a substring that matches the regular expression
search() Retrieve substrings in a string that match a regular expression. If no match is found, -1 is returned.
slice(start, end) Intercept the substring according to the following table
-
substring(start, end) Intercept the substring according to the following table
- ##split() Split the string into multiple substrings according to the specified delimiter and return the element group
substr( start, length) Truncate the string according to its length
- toUpperCase() Return a string in which all letters in the string are converted to uppercase letters.
- toLowerCase() Returns a string in which all letters are converted to lowercase letters.
- Methods of Math object
- ceil() Round up.
- round() Rounding.
- random() Get a random number.
- Methods of Date object
- getDate function: Returns the "day" part of the date, with values ranging from 1 to 31.
- getHours function: Returns the "hour" part of the date, the value is 0~23.
- getMinutes function: Returns the "minutes" part of the date, the value is 0~59.
- getMonth function: Returns the "month" part of the date, with values ranging from 0 to 11.
- getSeconds function: Returns the "seconds" part of the date, the value is 0~59.
- getTime function: Returns the system time.
- getTimezoneOffset function: Returns the time difference in this area (the regional time difference between local time and GMT Greenwich Mean Time), in minutes.
- getYear function: Returns the "year" part of the date. The return value is based on 1900, for example, 1999 is 99.
parse function: Returns the number of milliseconds since 0:00 on January 1, 1970 (local time)
setDate function: Set date The "day" part has a value of 0 to 31.
setHours function: Set the "hour" part of the date, the value is 0~23.
setMinutes function: Set the "minutes" part of the date, the value is 0~59.
setMonth function: Set the "month" part of the date, the value is 0~11. Among them, 0 represents January, ..., and 11 represents December.
setSeconds function: Set the "seconds" part of the date, the value is 0~59.
setTime function: Set time. The time value is the number of milliseconds since 00:00 on January 1, 1970.
setYear function: Set the "year" part of the date.
toGMTString function: Convert the date into a string, which is GMT Greenwich Mean Time.
setLocaleString function: Convert the date into a string, which is the local time.
- ##UTC function: Returns the number of milliseconds (GMT) since 0:00 on January 1, 1970.
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