img-resize.js

/**
 * 根据容器宽高和当前图片宽高确定适应宽高
 * @param conW 容器宽度
 * @param conH 容器高度
 * @param imgW 图片宽度
 * @param imgH 图片高度
 * @returns {{w: *, h: *}}
 */
getImgResize: function( conW, conH, imgW, imgH ){
    if( imgW <= conW && imgH <= conH ){
        return {
            w: imgW,
            h: imgH
        };
    }
    else {
        var width = imgW * 1.0;
        var height = imgH * 1.0;
        if(( width / conW ) > ( height / conH )){
            var new_width = conW;
            var new_height = parseInt( conW * height / width, 0);
        }
        else {
            new_width = parseInt( conH * width / height, 0 );
            new_height = conH;
        }

        return {
            w: new_width,
            h: new_height
        };
    }
}