这是我的方法:

var imgSrc, imgW, imgH;

function myFunction(image) {
    var img = new Image();
    img.src = image;
    img.onload = function() {
        return {
            src: image,
            width: this.width,
            height: this.height};
        }
    return img;
}

var x = myFunction('http://www.google.com/intl/en_ALL/images/logo.gif');
    // Waiting for the image loaded. Otherwise, system returned 0 as both width and height.
x.addEventListener('load', function() {
    imgSrc = x.src;
    imgW = x.width;
    imgH = x.height;
});

x.addEventListener('load', function() {
    console.log(imgW + 'x' + imgH); // 276x110
});
console.log(imgW); // undefined.
console.log(imgH); // undefined.
console.log(imgSrc); // undefined.

Use

function outmeInside() {
    var output = document.getElementById('preview_product_image');

    if (this.height < 600 || this.width < 600) {
        output.src = "http://localhost/danieladenew/uploads/no-photo.jpg";
        alert("The image you have selected is low resolution image. Your image width=" + this.width + ", height=" + this.height + ". Please select image greater or equal to 600x600. Thanks!");
    }
    else {
        output.src = URL.createObjectURL(event.target.files[0]);
    }
    return;
}



    img.src = URL.createObjectURL(event.target.files[0]);
}

这适用于多个图像预览和上传。如果你必须为每个图像逐一选择，然后复制粘贴到所有预览图像功能和验证!!

在使用真实图像大小之前，您应该加载源图像。如果使用jQuery框架，可以以简单的方式获得真实图像大小。

$("ImageID").load(function(){
  console.log($(this).width() + "x" + $(this).height())
})

此外(除了Rex和Ian的回答)还有:

imageElement.naturalHeight

and

imageElement.naturalWidth

它们提供了图像文件本身的高度和宽度(而不仅仅是图像元素)。

这个答案正是我所寻找的(在jQuery):

var imageNaturalWidth = $('image-selector').prop('naturalWidth');
var imageNaturalHeight = $('image-selector').prop('naturalHeight');

最近我有同样的问题，在一个错误的伸缩滑块。由于加载延迟，第一张图像的高度被设置得较小。我尝试了以下方法来解决这个问题，它是有效的。

// Create an image with a reference id. Id shall
// be used for removing it from the DOM later.
var tempImg = $('<img id="testImage" />');
// If you want to get the height with respect to any specific width you set.
// I used window width here.
tempImg.css('width', window.innerWidth);
tempImg[0].onload = function () {
    $(this).css('height', 'auto').css('display', 'none');
    var imgHeight = $(this).height();
    // Remove it if you don't want this image anymore.
    $('#testImage').remove();
}

// Append to body

$('body').append(tempImg);
// Set an image URL. I am using an image which I got from Google.
tempImg[0].src ='http://aspo.org/wp-content/uploads/strips.jpg';

这将为您提供相对于您设置的宽度的高度，而不是原始宽度或零。