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debugging JavaScript using Console.table ()

Source: Internet
Author: User
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Perhaps you have been accustomed to Console.log () to debug JS, very useful, but today Weibo see console.table () Debugging JavaScript, and Console.log () similar, the main difference is:

Mainly used to output objects and arrays;
More direct visualization, in tabular form;
You can output one or a few properties individually

Cases

The code is as follows Copy Code

<!doctype html>
<meta charset= "Utf-8" >
<body>
<script>
/**
*
* @authors Benjamin
* @date 2013-11-18 13:08:18
* Console.table () debugging JavaScript
* Directly into the instance
*/
Define an Object
var obj = {
"Name": "John",
"Age": 20,
"Sex": "Male"
};
Console.log ("------obj------");
Console.log ("Console.log () Print:");
Console.log (obj);
Console.log ("console.table print:");
Console.table (obj);

Define an array
var arr = ["AA", "BB", "CC", "DD"];
Console.log ("------arr------");
Console.log ("Console.log () Print:");
Console.log (arr);
Console.log ("console.table print:");
Console.table (arr);

Define a multidimensional array
var arr = ["AA", "BB", "CC", "DD", ["ee", "FF", "GG", ["HH", "II"]]];
Console.log ("------arr------");
Console.log ("Console.log () Print:");
Console.log (arr);
Console.log ("console.table print:");
Console.table (arr);

Define an array of objects
var Objarr = [{
"Name": "John",
"Age": 20,
"Sex": "Male"
},{
"Name": "John",
"Age": 20,
"Sex": "Male"
}];
Console.log ("------objarr------");
Console.log ("Console.log () Print:");
Console.log (Objarr);
Console.log ("console.table print:");
Console.table (Objarr);

Define a Multilevel Object array
var Objgradearr = [{
"Name": "John",
"Age": 20,
"Sex": "Male",
"Attribute": {
"A": "AA",
"B": "BB",
"C": "CC"
}
},{
"Name": "John",
"Age": 20,
"Sex": "Male",
"Attribute": {
"A": "Aa2",
"B": "Bb2",
"C": "CC2"
}
}];
Console.log ("------objgradearr------");
Console.log ("Console.log () Print:");
Console.log (Objgradearr);
Console.log ("console.table print:");
Console.table (Objgradearr);
</script>
</body>

Because I am not good at English translation, directly behind the English address you can enter the reference.

Imagine you have created this list of programming languages and their file extensions:

The code is as follows Copy Code

var languages = [
{Name: "JavaScript", FileExtension: ". js"},
{name: ' typescript ', fileextension: '. ts '},
{Name: "Coffeescript", FileExtension: ". Coffee"}
];

Console.log (languages);

The Console.log () call would give you the following representation of your data:

That tree view is helpful for debugging purposes, but I find it a little cumbersome to have to open every object manually. I ' m saying we can do a little better with console.table ().

Logging Array Data with console.table ()
Instead of calling Console.log (), we ll use Console.table () Now:

Console.table (languages);
Make sure the "console is opened before refreshing the" page, otherwise you won ' t to any output. If you are did everything correct, you'll be rewarded with this nice, little table view:

Pretty neat, isn ' t it?

Of course, tables work best for tabular data. If all the objects have a totally different structure, you'll end up with most of the cells containing values. Still, the property values are neatly arranged and give you a good overview.

Logging Object Data with console.table ()
Another nice thing about console.table () are that it also works with objects:

The code is as follows Copy Code

var languages = {
CSharp: {name: "C #", Paradigm: "object-oriented"},
FSharp: {name: "F #", Paradigm: "Functional"}
};

Console.table (languages);


' Nuff said.

Filtering the displayed Object Properties
If you are want to restrict the columns to certain properties, you can have a array of their keys as a second parameter to th e console.table () Call:

The code is as follows Copy Code

Multiple Property keys
Console.table (languages, ["Name", "Paradigm"]);
For a single, a simple string is sufficient:

A Single Property key
Console.table (Languages, "name");

If you do not understand on the, can enter to see English: http://www.mariusschulz.com/2013/11/13/advanced-javascript-debugging-with-consoletable

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