JavaScript Learning Essays

1. Operators
String stitching with "+"
Symbol "| |"

2.arr.length//Array length
STR.SUBSTR (2,3); Reads a few characters from a string, three characters from the third position in Str
Arr.join (); Separates array elements with symbols
Arr.split (); Separating strings by symbols

3. String objects
Str.indexof (); Returns the position of the substring, or 1 if not found
Date Day Object
var date = new Date ();
Dete.getfullyear ();
Math Object//method name directly with
Math.floor (2.3); 2
Math.random (); Back to [0,1]
Array Object

4.window objects
Window.alert (' Pop-up window ');
Window.confirm (' confirmation ');
Window.navigator//Browser information
Window.location.href= ""; Jump to a webpage
Window.history//Browsing history
Window.screen//Screen Object
Window.document//Document object (important)

5. Node operation
Find an Object
Find by ID, return value is Object
document.getElementById (' one ');
Search by label, return value is a collection of objects
document.getElementsByTagName (' P ');
For form elements, you can query by name, and the return value is a list of nodes (object collection).
Document.getelementsbyname (' Form1 ');
Search by class name, return object collection
Document.getelementsbyclassname (' Form1 ');
Find sub-object chlidren,parent
document.getElementById (' one '). ChildNodes;
document.getElementById (' one '). Children; Children non-standard attributes, excluding white space nodes

6. Get the run-time style object
Calculates the style of obj
function GetStyle (obj, attr) {
Return Obj.currentstyle? OBJ.CURRENTSTYLE[ATTR]: window.getcomputedstyle (obj, null) [attr];
}

7. Deleting objects
Steps: 1. Locate the object 2. Find his parent object Parentobj 3.parentobj.removechild (sub-object);
<script>
Function del () {
var lis = document.getelementsbytagname (' li ');
var lastli = lis[lis.length-1];
Lastli.parentNode.removeChild (Lastli);
}
</script>

8. Create a Node
1. Create object 2. Locate the Parent object Parentobj 3.parentobj.addchild (object);
function Add () {
var li = document.createelement (' li ');
var tex = document.createTextNode (' four ');
Li.appendchild (Tex);
document.getElementsByTagName (' ul ') [0].appendchild (LI);
}

9. Violent Operation node
function Add3 () {
var ul = document.getElementsByTagName (' ul ') [0];
ul.innerhtml = ' <li>one</li><li>two</li><li>three</li> ';
}

10. Linkage Menu
DOM Manipulation Events
OnChange ();
09.html

11. Timers
Window.settimeout (' Change () ', 1000); Perform change after 1 seconds ();
Cleartimeout ();
SetInterval (' Change () ', 1000); Change is performed every 1 seconds ();
Clearinterval ();

12. Common Events
OnClick//element when clicked
onfocus//element when getting focus
onblur//element loses focus
onmouseover//Move mouse over element
onmouseout//mouse over element
onsubmit = "Return Change ()"//form is submitted in form
OnLoad//page loading Complete Window.onlod = function change () {} or written in body

13. Event Behavior Structure separation
14.html

14.//Event Object
event = Window.enent | | Event
Event delegate
Ev.target

15. Regular Verification Mailbox
Patt.test (String);
Find the string that matches the regular character in the string
Regular Match Mailbox
Patt.exec (String);

JavaScript Learning Essays