多维表格
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

94 lines
2.8 KiB

export const createThumbnail = async (file: File): Promise<string | null> => {
if (!file.type.startsWith('image/') && !file.type.startsWith('video/')) return null
return new Promise<string | null>((resolve, reject) => {
const reader = new FileReader()
reader.onload = function (event) {
const thumbnailURL = event.target?.result as string
if (file.type.startsWith('image/')) {
const img = new Image()
img.onload = function () {
const canvas = document.createElement('canvas')
const ctx = canvas.getContext('2d')
if (!ctx) return resolve(null)
const thumbnailWidth = 200
const scaleFactor = thumbnailWidth / img.width
const thumbnailHeight = img.height * scaleFactor
canvas.width = thumbnailWidth
canvas.height = thumbnailHeight
ctx.drawImage(img, 0, 0, thumbnailWidth, thumbnailHeight)
const thumbnailDataURL = canvas.toDataURL('image/png')
resolve(thumbnailDataURL)
}
img.onerror = function () {
console.error('Error loading image')
reject(null)
}
img.src = thumbnailURL
} else if (file.type.startsWith('video/')) {
const video = document.createElement('video')
video.onloadedmetadata = function () {
video.currentTime = 1
}
video.onseeked = function () {
const canvas = document.createElement('canvas')
const ctx = canvas.getContext('2d')
if (!ctx) return resolve(null)
const thumbnailWidth = 200
const scaleFactor = thumbnailWidth / video.videoWidth
const thumbnailHeight = video.videoHeight * scaleFactor
canvas.width = thumbnailWidth
canvas.height = thumbnailHeight
ctx.drawImage(video, 0, 0, thumbnailWidth, thumbnailHeight)
const thumbnailDataURL = canvas.toDataURL('image/png')
resolve(thumbnailDataURL)
}
video.onerror = function () {
console.error('Error loading video')
reject(null)
}
video.src = thumbnailURL
} else {
resolve(null)
}
}
reader.onerror = function () {
console.error('Error reading file')
reject(null)
}
reader.readAsDataURL(file)
})
}
export async function isURLExpired(url?: string) {
if (!url) return { isExpired: false, status: 0, error: 'URL is empty' }
try {
const response = await fetch(url, {
method: 'GET',
headers: {
Range: 'bytes=0-0', // Request only the first byte
},
cache: 'no-store',
})
return {
isExpired: response.status === 403,
status: response.status,
}
} catch (error) {
return {
isExpired: true,
status: 0,
error: error.message,
}
}
}