front/uni_modules/uview-next/components/u-upload/utils.js

function compressImageForH5(options) {
	const {
		src,
		quality = 0.8,
		width = 'auto',
		height = 'auto',
		compressedWidth,
		compressedHeight,
		success,
		fail
	} = options;

	const img = new Image();
	img.crossOrigin = 'anonymous';
	
	img.onload = function() {
		try {
			const canvas = document.createElement('canvas');
			const ctx = canvas.getContext('2d');
			
			// 计算压缩后的尺寸
			let targetWidth = img.width;
			let targetHeight = img.height;
			
			// 优先使用 compressedWidth 和 compressedHeight
			if (compressedWidth && compressedHeight) {
				targetWidth = compressedWidth;
				targetHeight = compressedHeight;
			} else if (compressedWidth) {
				targetWidth = compressedWidth;
				targetHeight = (img.height * compressedWidth) / img.width;
			} else if (compressedHeight) {
				targetHeight = compressedHeight;
				targetWidth = (img.width * compressedHeight) / img.height;
			} else {
				// 处理 width 和 height 参数
				if (width !== 'auto') {
					if (width.includes('px')) {
						targetWidth = parseInt(width);
					} else if (width.includes('%')) {
						targetWidth = img.width * (parseInt(width) / 100);
					}
				}
				
				if (height !== 'auto') {
					if (height.includes('px')) {
						targetHeight = parseInt(height);
					} else if (height.includes('%')) {
						targetHeight = img.height * (parseInt(height) / 100);
					}
				}
				
				// 如果只设置了一个维度，等比缩放
				if (width !== 'auto' && height === 'auto') {
					targetHeight = (img.height * targetWidth) / img.width;
				} else if (height !== 'auto' && width === 'auto') {
					targetWidth = (img.width * targetHeight) / img.height;
				}
			}
			
			canvas.width = targetWidth;
			canvas.height = targetHeight;
			
			// 绘制压缩后的图片
			ctx.drawImage(img, 0, 0, targetWidth, targetHeight);
			
			// 转换为 blob
			canvas.toBlob((blob) => {
				if (blob) {
					success({
						tempFilePath: URL.createObjectURL(blob)
					})
				} else {
					fail(new Error('图片压缩失败'));
				}
			}, 'image/jpeg', quality);
			
		} catch (error) {
			fail(error);
		}
	};
	
	img.onerror = function() {
		fail(new Error('图片加载失败'));
	};
	
	img.src = src;
}

function pickExclude(obj, keys) {
	// 某些情况下，type可能会为
    if (!['[object Object]', '[object File]'].includes(Object.prototype.toString.call(obj))) {
        return {}
    }
    return Object.keys(obj).reduce((prev, key) => {
        if (!keys.includes(key)) {
            prev[key] = obj[key]
        }
        return prev
    }, {})
}

async function compressImages(config, files) {
	
	if( config === false){
		return files;
	}

	const tasks = [];
	for(let i = 0; i < files.length; i++) {
		tasks.push(new Promise((resolve) => {
			const options = {
				...config,
				src: files[i].url,
				fail:()=>{},
				success: (result) => {
					resolve(result);
				},
				fail: () => { 
					resolve('');
				}
			};

			// #ifndef H5
			uni.compressImage(options);
			// #endif

			// #ifdef H5
			compressImageForH5(options);
			// #endif
		}));
	}
	const results = await Promise.all(tasks);

	for(let i = 0; i < files.length; i++) {
		if(results[i]) {
			files[i].url = results[i].tempFilePath;
			files[i].thumb = results[i].tempFilePath;
		}
	}

	return files;
}

function formatImage(res) {
    return res.tempFiles.map((item) => ({
        ...pickExclude(item, ['path']),
        type: 'image',
        url: item.path,
        thumb: item.path,
		size: item.size,
		// #ifdef H5
		name: item.name
		// #endif
    }))
}

function formatVideo(res) {
    return [
        {
            ...pickExclude(res, ['tempFilePath', 'thumbTempFilePath', 'errMsg']),
            type: 'video',
            url: res.tempFilePath,
            thumb: res.thumbTempFilePath,
			size: res.size,
			// #ifdef H5
			name: res.name
			// #endif
        }
    ]
}

function formatMedia(res) {
    return res.tempFiles.map((item) => ({
        ...pickExclude(item, ['fileType', 'thumbTempFilePath', 'tempFilePath']),
        type: res.type,
        url: item.tempFilePath,
        thumb: res.type === 'video' ? item.thumbTempFilePath : item.tempFilePath,
		size: item.size
    }))
}

function formatFile(res) {
    return res.tempFiles.map((item) => ({ 
		...pickExclude(item, ['path']), 
		url: item.path, 
		size:item.size,
		// #ifdef H5
		name: item.name,
		type: item.type
		// #endif 
	}))
}
export function chooseFile({
    accept,
    multiple,
    capture,
    compressed,
    compressImage,
    maxDuration,
    sizeType,
    camera,
    maxCount
}) {
    return new Promise((resolve, reject) => {
        
        switch (accept) {
        case 'image':
            uni.chooseImage({
                count: multiple ? Math.min(maxCount, 9) : 1,
                sourceType: capture,
                sizeType,
                success: (res) => resolve(compressImages(compressImage,formatImage(res))),
                fail: reject
            })
            break
            // #ifdef MP-WEIXIN
            // 只有微信小程序才支持chooseMedia接口
        case 'media':
            wx.chooseMedia({
                count: multiple ? Math.min(maxCount, 9) : 1,
                sourceType: capture,
                maxDuration,
                sizeType,
                camera,
                success: (res) => resolve(formatMedia(res)),
                fail: reject
            })
            break
            // #endif
        case 'video':
            uni.chooseVideo({
                sourceType: capture,
                compressed,
                maxDuration,
                camera,
                success: (res) => resolve(formatVideo(res)),
                fail: reject
            })
            break
            // #ifdef MP-WEIXIN || H5
            // 只有微信小程序才支持chooseMessageFile接口
        case 'file':
            // #ifdef MP-WEIXIN
            wx.chooseMessageFile({
                count: multiple ? maxCount : 1,
                type: accept,
                success: (res) => resolve(formatFile(res)),
                fail: reject
            })
            // #endif
            // #ifdef H5
            // 需要hx2.9.9以上才支持uni.chooseFile
            uni.chooseFile({
                count: multiple ? maxCount : 1,
                type: accept,
                success: (res) => resolve(formatFile(res)),
                fail: reject
            })
            // #endif
            break
				// #endif
		default: 
			// 此为保底选项，在accept不为上面任意一项的时候选取全部文件
			// #ifdef MP-WEIXIN
			wx.chooseMessageFile({
			    count: multiple ? maxCount : 1,
			    type: 'all',
			    success: (res) => resolve(formatFile(res)),
			    fail: reject
			})
			// #endif
			// #ifdef H5
			// 需要hx2.9.9以上才支持uni.chooseFile
			uni.chooseFile({
				count: multiple ? maxCount : 1,
				type: 'all',
				success: (res) => resolve(formatFile(res)),
				fail: reject
			})
			// #endif
        }
    })
}