Javascript Object Property method summary_javascript tips-js tutorial

This article provides a detailed summary of Javascript Object attribute methods. For more information, see. Array: an ordered set of series Elements

Attribute:

Length: used to obtain the number of array elements, that is, the maximum subscript plus 1

Method:

Sort (function): If no sorting number is specified, it is arranged alphabetically by the elements. If it is not a string type, it is converted to a string;

Reverse (): reverses the order of elements in the array;

Concat (array1, arrayn): Used to combine N numbers and add them to the array1 array;

Join (string): Used to merge the elements in the array into a string, and the string is the separator. If any parameter is omitted, the elements are directly merged without additional points;

Slice (start, stop): Used to return the elements from start to stop in the array. If the parameter is negative, it indicates the reciprocal start or stop element;

ToString (): returns a string of all elements in the array separated by commas;

String)

Attribute:

Length: returns the length of a string. It is used in the same way as an array;

Method:

Anchor (): This method creates a tag in the same format as the anchor in HTML. Use the following method to access string. anchor (chorName)

ToUpperCase (): converts a string to uppercase;

ToLowerCase (): converts a string to lowercase;

IndexOf (a, B): searches for the position where character a appears in the string from character B and returns the result. If B is omitted, it searches from position 0 by default;

ChartAt (I): returns the I-th character in the string;

Substring (start, end): returns all characters in the string between start and end (but does not return the character of end itself );

Sub (): displays the specified string in subscript format;

Date: For details, see

Definition method:

A: var newdt = new Date () --> Create a time object and assign a value to the current time;
B: var newdt = new Date (milliseconds) --> Create time object, and set the object Value in milliseconds Based on the delay time of GTM;
C: var newdt = new Date (string) --> assign values to the newly created time object using a specific time string. The format matches the parse method of the Date object;
D: var newdt = new Date (year, month, day, hour, minute, second, millisecond) --> by year, month, day, hour, minute, second, assign values to objects in milliseconds;

Method: get time, set time, format conversion

A: Get time

GetDate () ----- get the current complete time;
GetYear () ------ get the current year
GetMonths () ---- get the current month
GetDay () ------- get the current date day
GetHours () ----- get the current hour
GetMinutes () --- get the current minute
GetSeconds () --- get the current second
GetTime () ------ get the current time, in seconds
GetTimeZoneOffset -- get the current time zone offset Information

B: set the time.

Replace get with set, for example, getDate () ---> setDate ()

C: Conversion Method

ToGTMString () ------ convert to the string of the Greenwich Mean Time expression;
ToLocaleString () ---- convert to a string expressed locally
ToString () ---------- convert time to string
Parse --------------- read the time from the string that represents the time
UTC ----------------- returns the gap from Greenwich Mean Time to the specified time, in milliseconds

Math mathematics:

Attribute: note that attributes in a mathematical object refer to read attributes.

E (= 2.7182) ------ bottom of the natural logarithm (I don't understand what it means, alas, I don't understand anything close to mathematics, I'm depressed !)
LN10 (= 2.30259) --- the natural logarithm of 10;
LN2 (= 0.69315) ----- natural logarithm of 2;
PI (= 3.1415926) ---- circumference Rate
SQRT1_2 (= 0.7071) -- square root of 1/2
SQRT2 (= 1.4142) ---- the square root of 2
LOG2E (= 1.44269) --- base on 2, logarithm of E
LOG10E (= 0.43429) -- base 10 logarithm of E

Method: Actually, I don't have much to use. I'm depressed. Let's get it all out.

Sin (a) ---- returns the sine of.
Cos (a) ------ calculate the cosine of
Tan (a) ------ returns the tangent of
Asin (a) ----- returns the arc sine of.
Atan (a) ----- returns the arc cosine of.
Exp (a) ------ calculate the index of
Log (a) ------ calculate the natural logarithm of
Pow (a, I) ---- calculate the I power of a (multiplication)
Round (a) ---- rounding
Sqrt (a) ----- calculate the square root of
Abs (a) ------ calculate the absolute value of
Random () ---- random Number
Max (a, B) ---- take a large number
Min (a, B) ---- take a smaller number

Note: All function parameters are of the floating point type. The trigonometric function parameters are radians, rather than degrees.

JavaScript built-in functions

Escape () and unescape (): encoding and decoding strings

Eval (string): used to execute operations or statements represented by strings
For example: var a = 0; var str1 = "a + = a"; eval (str1 );

ParseInt () and parseFloat (): Convert the value of the text box to an integer or floating point number.

Note: parseInt () is not used to round the number, but to cut the end.

IsNaN (): The complete E is (is not a number). As the name suggests, it is used to determine whether the string is a number, for example, if (isNaN ("tianbang series tutorial "))

Custom object: There are two methods to initialize objects and define constructor objects.

A: initialization object

For example, object = {property 1: value 1; Property 2: Value 2;... property n: value n}. Note that each property value pair is separated by a semicolon;

B: define the object of the constructor.

For example:
Function Name (attribute 1, attribute 2 ,... Attribute N ){

This. Attribute 1 = attribute value 1;
This. Attribute 2 = attribute value 2;
This. Attribute n = attribute value n;

This. method name 1 = function name 1;
This. method name 2 = function name 2;
}

Note: The method name and function name can have the same name. However, before calling a function, the function must be defined. Otherwise, an error occurs.

The new statement is used to create a new instance for a custom function.

Browser object

Window object:He belongs to the central level and is at the highest level of all objects. To put it bluntly, you can play without him;

Attribute:

Closed ---------- used to determine whether the window is closed;
Er ---------- store () method to open the parent window of the window;
Defaultstatus --- information displayed by default in the status bar;
Status ---------- information currently displayed in the status bar;
Document, Location, History --- very important. If you don't want to wait for it, read it here.

Method:

Alert (text) ------------- a prompt box is displayed.
Confirm (text) ----------- confirmation information box, the parameter is confirmation Information
Prompt (text, default) ---- the input dialog box is displayed. The parameters are the prompt information and default values.


Document Object:Includes various features of the current webpage, such as the title URL, background, language, and modification time.

Attribute:

Title ------------ document title
LastModified ----- last modification time of the object
URL -------------- URL of the document
Cookie ----------- create and obtain Cookie Information
BgColor ---------- background color of the document
FgColor ---------- foreground color of the document
Location --------- save all the page address information of the document
Alinkcolor ------- activation connection color
Linkcolor -------- link color
Vlinkcolor ------- color of the browsed Link

Method:

Write (text) ----- write text or labels to the document without line breaks
Writeln (text) --- write text or tags to the document and wrap the line at the last character
() ---------- Open a new document, for example ("Address", "window name", "style ")
Close () --------- close the current document

Location object:Contains all the page addresses of the current document

Attribute:

Protocol ----------- communication protocol
Host --------------- host Name of the WEB server where the page is located
Port --------------- port number for server communication
Pathname ----------- path of the document on the server
Hash --------------- information about the page Jump anchor tag
Searce ------------- information submitted to the server for search
Hostname ----------- host name and port number, separated by a colon
Href --------------- complete URL

Method:

Assign (URL) -------- navigate the page to another address
Reload ------------- refresh the page
Replace (URL) ------- replace the current page with the specified URL

History:This object includes previously accessed URL Information

Attribute: length, number of returned URLs

The main method is go (n). This method is used to load the relative page.