问响应图像源取决于介质

EN

var timeout=0;
$(window).resize(function(){
    clearTimeout(timeout);
    timeout=setTimeout(function(){
        resizeWindow();
    },500);
});

function resizeWindow(){
    var windowWidth=$(window).width();
    switch(true){
        case(windowWidth<750):/* you could specify other sizes to suit your needs*/
            $("img").each(function(){
                if($(this).attr("data-xs-src")){
                    $(this).attr("src",$(this).attr("data-xs-src"))
                }
            })
        break;
        default:
            $("img").each(function(){
                if($(this).attr("data-default-src")){
                    $(this).attr("src",$(this).attr("data-default-src"))
                }
            })
    }
}
resizeWindow();//use setTimeout if js code is in header

<img data-default-src="images/img.jpg"  data-xs-src="images/xsimg.jpg" >