javascript - 在网页上显示标题或替代文本

Question

目前，我的网站上有一个幻灯片，显示了作品集的一些图像。它效果很好，但现在我想在单独的框/div 中使用图像下方的替代文本或标题添加标题。

这可能吗？如果是这样，有人知道有任何教程或资源可以实现这一目标吗？

目前这就是我显示图像的方式

<ul class="slides">
                        <li><img src="Pictures/1.jpg" width="400" height="200" title = ""alt="Marsa Alam underawter close up" /></li>
                        <li><img src="Pictures/2.jpg" width="400" height="200" alt="Marsa Alam underawtzxcxzczxczxczxczer close up" /></li>
                        <li><img src="Pictures/4.jpg" width="400" height="200" alt="Marsa Alam underawccccter close up" /></li>
                        <li><img src="Pictures/3.jpg" width="400" height="200" alt="Marsa Alam underawtcxzczxcxzczcxcxzcer close up" /></li>

                    </ul>

要循环浏览图像，请使用此脚本 http://tutorialzine.com/2010/09/html5-canvas-slideshow-jquery/

$(window).load(function(){

    // We are listening to the window.load event, so we can be sure
    // that the images in the slideshow are loaded properly.


    // Testing wether the current browser supports the canvas element:
    var supportCanvas = 'getContext' in document.createElement('canvas');

    // The canvas manipulations of the images are CPU intensive,
    // this is why we are using setTimeout to make them asynchronous
    // and improve the responsiveness of the page.

    var slides = $('#slideshow li'),
        current = 0,
        slideshow = {width:0,height:0};

    setTimeout(function(){

        window.console && window.console.time && console.time('Generated In');

        if(supportCanvas){
            $('#slideshow img').each(function(){

                if(!slideshow.width){
                    // Taking the dimensions of the first image:
                    slideshow.width = this.width;
                    slideshow.height = this.height;
                }

                // Rendering the modified versions of the images:
                createCanvasOverlay(this);
            });
        }

        window.console && window.console.timeEnd && console.timeEnd('Generated In');

        $('#slideshow .arrow').click(function(){
            var li          = slides.eq(current),
                canvas      = li.find('canvas'),
                nextIndex   = 0;

            // Depending on whether this is the next or previous
            // arrow, calculate the index of the next slide accordingly.

            if($(this).hasClass('next')){
                nextIndex = current >= slides.length-1 ? 0 : current+1;
            }
            else {
                nextIndex = current <= 0 ? slides.length-1 : current-1;
            }

            var next = slides.eq(nextIndex);

            if(supportCanvas){

                // This browser supports canvas, fade it into view:

                canvas.fadeIn(function(){

                    // Show the next slide below the current one:
                    next.show();
                    current = nextIndex;

                    // Fade the current slide out of view:
                    li.fadeOut(function(){
                        li.removeClass('slideActive');
                        canvas.hide();
                        next.addClass('slideActive');
                    });
                });
            }
            else {

                // This browser does not support canvas.
                // Use the plain version of the slideshow.

                current=nextIndex;
                next.addClass('slideActive').show();
                li.removeClass('slideActive').hide();
            }
        });

    },100);

    // This function takes an image and renders
    // a version of it similar to the Overlay blending
    // mode in Photoshop.

    function createCanvasOverlay(image){

        var canvas          = document.createElement('canvas'),
            canvasContext   = canvas.getContext("2d");

        // Make it the same size as the image
        canvas.width = slideshow.width;
        canvas.height = slideshow.height;

        // Drawing the default version of the image on the canvas:
        canvasContext.drawImage(image,0,0);


        // Taking the image data and storing it in the imageData array:
        var imageData   = canvasContext.getImageData(0,0,canvas.width,canvas.height),
            data        = imageData.data;

        // Loop through all the pixels in the imageData array, and modify
        // the red, green, and blue color values.

        for(var i = 0,z=data.length;i<z;i++){

            // The values for red, green and blue are consecutive elements
            // in the imageData array. We modify the three of them at once:

            data[i] = ((data[i] < 128) ? (2*data[i]*data[i] / 255) : (255 - 2 * (255 - data[i]) * (255 - data[i]) / 255));
            data[++i] = ((data[i] < 128) ? (2*data[i]*data[i] / 255) : (255 - 2 * (255 - data[i]) * (255 - data[i]) / 255));
            data[++i] = ((data[i] < 128) ? (2*data[i]*data[i] / 255) : (255 - 2 * (255 - data[i]) * (255 - data[i]) / 255));

            // After the RGB elements is the alpha value, but we leave it the same.
            ++i;
        }

        // Putting the modified imageData back to the canvas.
        canvasContext.putImageData(imageData,0,0);

        // Inserting the canvas in the DOM, before the image:
        image.parentNode.insertBefore(canvas,image);
    }

});

幻灯片的 CSS 在这里

#slideshow ul{
    height:310px;
    position:absolute;
    top:10px;
    width:410px;
}

#slideshow li{
    position:absolute;
    display:none;
    z-index:10;
    margin-left:-30px; 
    margin-top:-15px; 
}

#slideshow li:first-child{

    display:block;
    margin-left:-30px; 
    margin-top:-15px; 
}

#slideshow .slideActive{
    z-index:1000;
}

#slideshow canvas{
    display:none;
    position:absolute;
    z-index:100;
}


#slideshow .arrow{
    height:86px;
    width:60px;
    position:absolute;
    background:url('img/arrows.png') no-repeat;
    top:50%;
    margin-top:-43px;
    cursor:pointer;
    z-index:5000;
}

#slideshow .previous{ background-position:left top;left:0;}
#slideshow .previous:hover{ background-position:left bottom;}

#slideshow .next{ background-position:right top;right:0;}
#slideshow .next:hover{ background-position:right bottom;}

Answer 1

这样的东西应该可以工作，每个li中都会有一个span，其中包含来自alt的文本

var addTitle = function(){
    var alt = $('img', this).attr('alt');

    $(this).append('<span>' + alt + '</span>');
};

$('.slides li').each(addTitle);