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There are a lot of objects in JavaScript, and there are a few more explanations for what you feel.
Learn some books on the web and read JavaScript.
If you want this manual can leave a message, see I will send you. Well, here's a summary of my own object's approach to the next step.
1. Objects:
(1) All events in JavaScript are objects: strings, arrays, functions ...
(2) Each object has properties and methods.
(3) JS allows custom objects to be customized.
2. Custom objects:
(1) Define and create an object instance.
(2) Use a function to define the object, and then create a new object instance.
Example (for 2-(1)):
Method 1:
<script>
People=new Object ();
People.name= "Ying";
People.age= "18";
document.write ("Name:" +people.name+ ", Age:" +people.age);
</script>
Results: The interface prints out name: Ying, age:18
Method 2:
<script>
People=new Object ();
people={
Name: "Ying",
Age:18
}
document.write ("Name:" +people.name+ ", Age:" +people.age);
</script>
Results: The interface prints out name: Ying, age:18
Example (for 2-(2)):
<script>
function people (Name,age) {
This.name=name;
This.age=age;
}
Son=new people ("Ying", 18);
document.write ("Name:" +son.name+ ", Age:" +son.age);
</script>
Results: The interface prints out name: Ying, age:18
String String Object
1.string objects:
A string object is used to work with an existing string, and strings can be spread using either single or double quotes: mixed use to avoid conflicts. 】。
2. Some of the properties of the demo:
(1) Find the string in the string: IndexOf ()
Example (for 2-(1)):
<script>
var str= "Hello World";
document.write ("string:" +str.length+ "<br/>");
document.write ("World Position:" +str.indexof ("World") + "<br/>");
document.write ("llllll position" Str.indexof ("llllll"));
</script>
Result: The interface prints out a string: 11
World's Location: 6
Location of lllllll:-1
(2) Content matching: match ()
Example (for 2-(2)):
<script>
var str= "Hello World";
document.write (Str.match ("World"));
document.write (Str.match ("lllllll"));
</script>
Result: The interface prints out world null
(3) Replacement content: replace ()
Example (for 2-(3)):
<script>
var str= "Hello World";
document.write (Str.replace ("World", "123"));
</script>
Result: The interface prints Hello 123
(4) Uppercase conversion of Strings: toUpperCase ()/toLowerCase ()
Example (for 2-(4)):
<script>
var str= "Hello World";
document.write (Str.touppercase ());
</script>
Result: The interface prints out Hello World
(5) string to array: Split ()
Example (for 2-(5)):
<script>
var str1= "HELLO,JJJ,LLL,KKK";
var s=str1.split (",");//comma as delimiter
document.write (S[1]);
</script>
Results: Interface Printing JJJ
----------------------------------------------------
Date Date Object
1.Date objects:
Date objects are used to process dates and times.
2. Obtain the date of the day.
3. Some commonly used methods:
(1) getFullYear (): Gets the year.
(2) GetTime (): Gets milliseconds.
(3) setFullYear (): Set specific date.
(4) Getday (): Get week.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Example (for 3):
<script>
var date = new Date ();
document.write (date+ "<br/>");
document.write (Date.getfullyear () + "<br/>");
document.write (Date.gettime () + "<br/>");
document.write (Date.getday () + "<br/>");
Date.setfullyear (2010,1,1);
document.write (date);
</script>
Results:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4. Clock Example:
<script >
function StartTime () {
var today=new Date ();
var h=today.gethours ();
var m=today.getminutes ();
var s=today.getseconds ();
M=checktime (m);
S=checktime (s);
document.getElementById (' txt '). innerhtml=h+ ":" +m+ ":" +s;
T=settimeout (' StartTime () ', 500);//equal to T=settimeout (function () {startime;},500)
}
function Checktime (i) {
if (i<10) {
I= "0" + i;
}
return I
}
</script>
<body onload= "StartTime ()" >
<div id= "TXT" ></div>
</body>
Results: Dynamic Display time
Array object:
1.Array objects:
Use a separate variable to store a series of values.
2. The creation of the array:
Example: Var myarray=["KKK", "ddd", "ddddd"];
3. Array Access:
You can access a particular element by specifying the array name and the index number.
"NOTE: [0] is the first element of the array, and so on." 】
4. Common Methods for arrays:
(1) concat (): Merging arrays.
(2) sort (): sorting.
(3) Push (): Append element at end.
(4) reverse (): The element of the array is flipped.
Example (for 4-(1)):
<script>
var a=["AA", "BB"];
var b=["CC", "DD"];
var c=a.concat (b);
document.write (c);
</script>
Result: The interface prints out AA BB cc DD
Example (for 4-(2)):
<script>
var a=["A", "C", "D", "T", "B", "E"];
document.write (A.sort ());
</script>
Result: The interface prints out a b c e D t
Extension
<script>
var a=["5", "2", "3", "4", "1"];
document.write (A.sort (function (a,b) {return b-a;})
</script>
Results: The interface prints out 54321. (PS: Because b-a is in reverse order).
Example (for 4-(3)):
<script>
var a=["A", "B"];
A.push (c);
document.write (a);
</script>
Result: Print out ABC
Example (for 4-(4)):
<script>
var a=["C", "B", "a"];
document.write (A.reverse ());
</script>
Result: Print out ABC
Math object:
1.Match objects:
Perform common arithmetic tasks.
2. Common methods:
(1) Round (): rounded.
(2) Random (): Returns the random number between 0~1.
(3) Max (): Returns the highest value.
(4) min (): Returns the minimum value.
(5) ABS (): Returns absolute value.
Example (for 2-(1)):
document.write (Math.Round (2.5));
Result: The interface prints out 3
Example (for 2-(2)):
document.write (Math.randow ());
Results: The interface randomly prints out a number of 0~1.
document.write (Math.randow () *10);
Results: The interface randomly prints out a number of 1~10.
document.write (parseint (Math.randow ()));
Result: The interface randomly prints out a number of 0~1, and this number is an integer.
Example (for 2-(3)):
document.write (Math.max (10,20,3,90));
Result: The interface prints a maximum value of 90.
Example (for 2-(4)):
document.write (Math.min (12,0,2,3,4));
Result: The interface prints a minimum value of 0.
Example (for 2-(5)):
document.write (Math.Abs (-10));
Results: The interface prints out 10.
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