How to use the "go" JS keyword in

How to use the JS keyword in the original address: http://sunct.iteye.com/blog/1709017

1.For ... In declares a loop/iterate operation for an array or an object's properties.

For An array , iterate over the array element , and for the object , iterate over the object's attributes;

JS Code

1. var x
2. var mycars = new Array ()
3. Mycars[0] = "Saab"
4. MYCARS[1] = "Volvo"
5. MYCARS[2] = "BMW"
7. for (x in mycars)
8. {
9. document.write (Mycars[x] + "<br/>")
10. }

The output is:

Java code

1. Saab
2. Volvo
3. BMW

Object Example: JS code

1. var obj = {
2. W: "Wen",
3. J: "Jian",
4. B: "Bao"
5. }
6. for (var v in obj) {
7. document.write (v) +"<br/>";
9. }

Output as: Java code

1. W
2. J
3. B

2. Determine whether an object is an element/attribute of an array/object:Format: (variable in object) ... Attention

When an "object" is an array, "variable" refers to the "index" of the arrays;

When "Object" is an object, "variable" refers to the object's "Properties".

Examples of arrays:

JS Code

1. var arr = ["A","B","2","3","str"];
2. var result = ("b" in arr);
3. var result1 = (4 in arr);
4. document.write (result+"<br>");
5. document.write (result1+"<br>");

Output as: Java code

1. False
2. True

Object Example: JS code

2. var obj={
4. W:"Wen",
6. J:"Jian",
8. B:"Bao"
12. }
16. var result= (2 in obj);
18. var result1= ("J" in obj);
22. document.write (Result) +"<br/>";
24. document.write (RESULT1) +"<br/>";

Output as: Java code

1. False
2. True

How to use the "go" JS keyword in