1: The role of the array: only the batch of data needs to use the array declaration
Two: How to declare an array:
1: A quick way to declare an array
var array name = [element 1, element 2, . . ];
example:
var names = ["name", "age", "grade"];
var tems=["cab","10","11,true];
var arrs = {
["111","222"],
["aaa","bbbb"],
["333","ccc"]
};
alert(arrs[1][1]);
2. Declaration method:
Use Array objects
var arr = new Array("member", "member n");
var str="abc";
var str=new string("abc")
for...in: Use the for...in statement to loop through the elements in the output array concat(): concat() merges two arrays.
effect:
Dom（Documnet object Model）
1:document document html xml file (markup language)
<body>
<div>
<a>www</a>
</div>
</body>
2: object object (the object that the html element is converted into (js object))
If you use js to manipulate documents, you need to choose to convert the html document structure into js objects
a. Operational properties
b. Operation content
innerText(IE) textContent(FF)
innerHTML
outerText
outerHTML
Form:
value
c. Operation style
aobj.style.backgroundColor="red";
aobj.style.fontSize="3cm";
classname
aobj.classname="test";
aobj.classname+="demo";
aobj.calssName=""
With the above three points of operation, first convert it into an object
convert to object
1: tagname (multiple), id (unique), name (multiple)
Three methods in document
var objs=document.getElementByTagName("div");
var objs=document.getElementById("one");
var objs=document.getElementByName("two");
Array exercise:
<script>
var mycars = new Array()
mycars[0] = "Saab"
mycars[1] = "Volvo"
mycars[2] = "BMW"
for (i=0;i<mycars.length;i++)
{
document.write(mycars[i] + "<br />")
}
</script>