微信js 分享大图片不显示

// 使用canvas压缩图片
function compressImage(file, maxWidth, maxHeight, quality) {
    return new Promise((resolve, reject) => {
        const img = new Image();
        img.src = URL.createObjectURL(file);
        img.onload = () => {
            const canvas = document.createElement('canvas');
            let width = img.width;
            let height = img.height;

            if (width > height) {
                if (width > maxWidth) {
                    height *= maxWidth / width;
                    width = maxWidth;
                }
            } else {
                if (height > maxHeight) {
                    width *= maxHeight / height;
                    height = maxHeight;
                }
            }

            canvas.width = width;
            canvas.height = height;
            const ctx = canvas.getContext('2d');
            ctx.drawImage(img, 0, 0, width, height);

            canvas.toBlob((blob) => {
                resolve(blob);
            }, 'image/jpeg', quality);
        };
        img.onerror = reject;
    });
}

wx.config({
    // ...其他配置
    jsApiList: ['updateAppMessageShareData', 'updateTimelineShareData']
});

wx.ready(function () {
    wx.updateAppMessageShareData({
        title: '分享标题',
        desc: '分享描述',
        link: 'http://yourdomain.com/page',
        imgUrl: 'http://yourdomain.com/path/to/image.jpg', // 确保是完整URL
        success: function () {
            // 设置成功
        }
    });
});

function preloadImage(url) {
    return new Promise((resolve, reject) => {
        const img = new Image();
        img.src = url;
        img.onload = resolve;
        img.onerror = reject;
    });
}

preloadImage('http://yourdomain.com/path/to/image.jpg').then(() => {
    wx.updateAppMessageShareData({
        // ...分享配置
    });
});

const imageUrl = 'http://yourdomain.com/path/to/image.jpg?t=' + Date.now();