有人知道如何将一个UIImage转换为Base64字符串,然后反转它吗?
我有以下代码;编码前的原始图像是好的,但编码解码后只得到一个空白图像。
NSData *imageData = UIImagePNGRepresentation(viewImage);
NSString *b64EncStr = [self encode: imageData];
NSString *base64String = [self encodeBase64:imageData];
有人知道如何将一个UIImage转换为Base64字符串,然后反转它吗?
我有以下代码;编码前的原始图像是好的,但编码解码后只得到一个空白图像。
NSData *imageData = UIImagePNGRepresentation(viewImage);
NSString *b64EncStr = [self encode: imageData];
NSString *base64String = [self encodeBase64:imageData];
当前回答
Swift版本-创建base64镜像
在我看来,在UIImagePNGRepresenatation()的情况下隐式Unwrapped Optional是不安全的,所以我建议使用扩展如下:
extension UIImage {
func toBase64() -> String? {
let imageData = UIImagePNGRepresentation(self)
return imageData?.base64EncodedStringWithOptions(NSDataBase64EncodingOptions.Encoding64CharacterLineLength)
}
}
其他回答
在Swift 3.0和Xcode 8.0
编码:
let userImage:UIImage = UIImage(named: "Your-Image_name")!
let imageData:NSData = UIImagePNGRepresentation(userImage)! as NSData
let dataImage = imageData.base64EncodedString(options: .lineLength64Characters)
解码:
let imageData = dataImage
let dataDecode:NSData = NSData(base64Encoded: imageData!, options:.ignoreUnknownCharacters)!
let avatarImage:UIImage = UIImage(data: dataDecode as Data)!
yourImageView.image = avatarImage
斯威夫特iOS8
// prgm mark ----
// convert images into base64 and keep them into string
func convertImageToBase64(image: UIImage) -> String {
var imageData = UIImagePNGRepresentation(image)
let base64String = imageData.base64EncodedStringWithOptions(.allZeros)
return base64String
}// end convertImageToBase64
// prgm mark ----
// convert images into base64 and keep them into string
func convertBase64ToImage(base64String: String) -> UIImage {
let decodedData = NSData(base64EncodedString: base64String, options: NSDataBase64DecodingOptions(rawValue: 0) )
var decodedimage = UIImage(data: decodedData!)
return decodedimage!
}// end convertBase64ToImage
@implementation UIImage (Extended)
- (NSString *)base64String {
NSData * data = [UIImagePNGRepresentation(self) base64EncodedDataWithOptions:NSDataBase64Encoding64CharacterLineLength];
return [NSString stringWithUTF8String:[data bytes]];
}
@end
很好理解你是否传递了Tyler Sheaffer所说的前缀。 但出于某种原因,你可能需要这个前缀来描述base64字符串开头的mime类型,所以我建议这段代码在编码之前传递一些选项(Swift 5):
extension UIImage {
enum Format: String {
case png = "png"
case jpeg = "jpeg"
}
func toBase64(type: Format = .jpeg, quality: CGFloat = 1, addMimePrefix: Bool = false) -> String? {
let imageData: Data?
switch type {
case .jpeg: imageData = jpegData(compressionQuality: quality)
case .png: imageData = pngData()
}
guard let data = imageData else { return nil }
let base64 = data.base64EncodedString(options: Data.Base64EncodingOptions.lineLength64Characters)
var result = base64
if addMimePrefix {
let prefix = "data:image/\(type.rawValue);base64,"
result = prefix + base64
}
return result
}
}
SWIFT 3.0, XCODE 8.0
将字符串替换为URL。和testImage是ImageView的一个出口
// Put Your Image URL
let url:NSURL = NSURL(string : "http://.jpg")!
// It Will turn Into Data
let imageData : NSData = NSData.init(contentsOf: url as URL)!
// Data Will Encode into Base64
let str64 = imageData.base64EncodedData(options: .lineLength64Characters)
// Now Base64 will Decode Here
let data: NSData = NSData(base64Encoded: str64 , options: .ignoreUnknownCharacters)!
// turn Decoded String into Data
let dataImage = UIImage(data: data as Data)
// pass the data image to image View.:)
testImage.image = dataImage
希望能有所帮助谢谢。