Navigator object

1、 What is? navigator object

navigator Object contains information about the browser .

see navigator Object all information ：

console.log(navigator);

Let's take the determination of whether a plug-in is installed in the browser as an example , To explain its usage .

stay navigator Among the many properties of the object , There is an attribute called Plugins, The plug-in information is stored inside , Through the following

View by ：

console.log(navigator.plugins);

Next, by encapsulating a method , To determine whether a plug-in is installed , If installed, return to true, Otherwise return to false.

    <script>
        function hasPlugin(name) {
            name = name ? name.toLocaleLowerCase() : '';
            console.log('name = ' + name);
            var plugins = navigator.plugins;
            for (var i = 0; i < plugins.length; i++) {
                //console.log(typeof plugins[i]);
                console.log(plugins[i].name);
                return plugins[i].name.toLocaleLowerCase().indexOf(name) !== -1 ? true : false;
            }
        }
        var r = hasPlugin('pdf');
        console.log(r);
    </script>

stay navigator There is another object called userAgent Attributes are more commonly used . It is generally used to obtain browser information .

This property returns the message sent by the client to the server user-agent The value of the head .

The following code can determine which terminal the user opens the page , Realize jump