Detailed description of access methods for JavaScript attributes

Access Method of JavaScript attributes
Copy codeThe Code is as follows:
Var fish = {
Head: 1,
Tail: 1,
Feature :{
Speak: false,
Swim: true
}
}

First, the vertex OPERATOR:
Copy codeThe Code is as follows:
Console. log (fish. head); // 1
Console. log (fish. tail); // 1
Console. log (fish. feature); // Object {head: 1, tail: 1, feature: Object}

Second, the [] OPERATOR:
Copy codeThe Code is as follows:
Console. log (fish ['head']); // 1

Note that the attribute name must be in the string format.
For example:
Copy codeThe Code is as follows:
Console. log (fish [head]); // error!

Is the following code correct?
Copy codeThe Code is as follows:
For (var prop in fish ){
Console. log (fish [prop]);
}

The answer is yes, because the property of the traversal object exists in the string type, that is, the prop is 'head', 'tail', and 'feature 'in sequence '.