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
对于Base64代码,例如:
"data:image/jpg;base64,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"
使用Swift5.0代码如下:
func imageFromBase64(_ base64: String) -> UIImage? {
if let url = URL(string: base64), let data = try? Data(contentsOf: url) {
return UIImage(data: data)
}
return nil
}
其他回答
在Swift 3.0中
func decodeBase64(toImage strEncodeData: String) -> UIImage {
let dataDecoded = NSData(base64Encoded: strEncodeData, options: NSData.Base64DecodingOptions.ignoreUnknownCharacters)!
let image = UIImage(data: dataDecoded as Data)
return image!
}
Swift 3.0和Xcode 8.0
let imageData = UIImageJPEGRepresentation(imageView.image!, 1)
let base64String = (imageData! as Data).base64EncodedString(options: NSData.Base64EncodingOptions(rawValue: 0))
print(base64String)
解码使用方便的初始化器- Swift 5
extension UIImage {
convenience init?(base64String: String) {
guard let data = Data(base64Encoded: base64String) else { return nil }
self.init(data: data)
}
}
对于Base64代码,例如:
"data:image/jpg;base64,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"
使用Swift5.0代码如下:
func imageFromBase64(_ base64: String) -> UIImage? {
if let url = URL(string: base64), let data = try? Data(contentsOf: url) {
return UIImage(data: data)
}
return nil
}
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)
}
}