JS and css are used to detect changes in the direction of mobile devices and determine whether the screen is horizontal or vertical.
This article mainly introduces JS and css implementation to detect changes in the direction of mobile devices and determine whether the screen is horizontal or vertical. This article provides implementation code respectively. For more information, see
Method 1: Use the trigger to switch between the portrait and landscape screens of the mobile phone
The Code is as follows:
Window. addEventListener ("orientationchange", function (){
// Announce the value of the new direction
Alert (window. orientation );
}, False );
Method 2: Change the listener size
The Code is as follows:
Window. addEventListener ("resize", function (){
// Obtain the screen size (internal/external width, internal/external height)
}, False );
Css screen Identification
The Code is as follows:
/* Portrait */
@ Media screen and (orientation: portrait ){
/* Portrait-specific styles */
}
/* Landscape */
@ Media screen and (orientation: landscape ){
/* Landscape-specific styles */
}
The local window. matchMedia method allows real-time media queries. We can use the preceding media queries to find that we are in an upright or horizontal view:
The Code is as follows:
Var mql = window. matchMedia ("(orientation: portrait )");
// If there is a match, we are in the vertical angle of view
If (mql. matches ){
// Orientation
Alert ("1 ")
} Else {
// Horizontal direction
Alert ("2 ")
}
// Add a media query to change the listener
Mql. addListener (function (m ){
If (m. matches ){
// Change to the upright direction
Document. getElementById ("test"). innerHTML = "change to upright direction ";
}
Else {
Document. getElementById ("test"). innerHTML = "change to horizontal direction ";
// Change to the horizontal direction
}
});