What are the topics of javascript?
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1, the running result of the following expression is:
["1", "2", "3"] .map (parseInt)
A. ["1", "2", "3"]
B. [1,2,3]
C. [0,1,2]
d. Other
2, the running result of the following expression is:
[typeof null, null instanceof Object]
A. ["object", false]
B. [null,false]
C. ["object", true]
d. Other
3, the running result of the following expression is:
[[3Jing 2 Jing 1] .reduce (Math.pow), [] .reduce (Math.pow)]
a. Error
B. [9,0]
C. [9,NaN]
D. [9,undefined]
4, the running result of the following expression is:
Var val = 'value'
Console.info ('Value id' + (val = = 'value')?' Something':'Nothing')
A.Something
B.Nothing
C.NaN
d. Other
5, the running result of the following expression is:
Var name = 'World'
(function () {
If (typeof name = = 'undefined') {
Var name = "Jack"
Console.info ('Goodbye' + name)
} else {
Console.info ('Hello' + name)
}
) ()
A.Goodbye Jack
B.Hello Jack
C.Goodbye undefined
D.Hello undefined
6, the running result of the following expression is:
Var START = END-100
Var count = 0
For (var I = START; I 0
A.true
B.false
c. Error
d. Other
23, the running result of the following expression is:
[1
