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Detailed explanation of js console.log printing object and array usage_javascript skills
Detailed explanation of js console.log printing object and array usage_javascript skills
The example in this article describes the usage of js console.log printing objects and arrays. Share it with everyone for your reference, the details are as follows:
What is console.log? It is actually a function that prints js arrays and objects, just like PHP's print_r and var_dump. There is nothing much to say about the console.log function itself. This blog will tell you how to use this function. Before talking about this function, I think the most commonly used one to check js output is alert, but alert can only play string or int
1. Test file test.html
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>console.log test</title>
</head>
<script type="text/javascript">
var testobj =
{
'id': 1,
'content': 'test',
'firstname': function() {
document.getElementById('firstname').value = "zhang";
},
'lastname': function() {
document.getElementById('lastname').value = "ying";
}
};
<!-- 打印对像 -->
console.log(testobj);
</script>
<body>
<input type="text" id='firstname' name="firstname" value=''>
<input type="text" id='lastname' name='lastname' value=''>
</body>
</html>
2. View js objects using chrome development tools
console chrome
Now when I use chrome developer tools and firebug, they are half and half. Chrome developer tools also have a feature that firebug does not have.
The console can run js. If the page is an iframe, firebug can only run on the parent, and chrome can choose the page inside to execute, as shown below
chrome iframe console
3. View js objects in firebug
firebug console
Readers who are interested in more content related to JavaScript arrays can check out the special topic on this site: "Summary of JavaScript array operation skills"
I hope this article will be helpful to everyone in JavaScript programming.
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