254

有谁知道如何将 a 转换UIImage为 Base64 字符串，然后将其反转？

我有以下代码；编码前的原始图像是好的，但我编码和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];
4

24 回答 24

604

迅速

首先我们需要有图像的 NSData

//Use image name from bundle to create NSData
let image : UIImage = UIImage(named:"imageNameHere")!
//Now use image to create into NSData format
let imageData:NSData = UIImagePNGRepresentation(image)!

//OR next possibility

//Use image's path to create NSData
let url:NSURL = NSURL(string : "urlHere")!
//Now use image to create into NSData format
let imageData:NSData = NSData.init(contentsOfURL: url)!

Swift 2.0 > 编码

let strBase64:String = imageData.base64EncodedStringWithOptions(.Encoding64CharacterLineLength)

Swift 2.0 > 解码

let dataDecoded:NSData = NSData(base64EncodedString: strBase64, options: NSDataBase64DecodingOptions.IgnoreUnknownCharacters)!

Swift 3.0 > 解码

let dataDecoded : Data = Data(base64Encoded: strBase64, options: .ignoreUnknownCharacters)!

编码：

let strBase64 = imageData.base64EncodedString(options: .lineLength64Characters)
print(strBase64)

解码：

let dataDecoded:NSData = NSData(base64EncodedString: strBase64, options: NSDataBase64DecodingOptions(rawValue: 0))!
let decodedimage:UIImage = UIImage(data: dataDecoded)!
print(decodedimage)
yourImageView.image = decodedimage

斯威夫特 3.0

let dataDecoded : Data = Data(base64Encoded: strBase64, options: .ignoreUnknownCharacters)!
let decodedimage = UIImage(data: dataDecoded)
yourImageView.image = decodedimage

Objective-C

iOS7 > 版本

您可以使用NSData's base64EncodedStringWithOptions

编码：

- (NSString *)encodeToBase64String:(UIImage *)image {
 return [UIImagePNGRepresentation(image) base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
}

解码：

- (UIImage *)decodeBase64ToImage:(NSString *)strEncodeData {
  NSData *data = [[NSData alloc]initWithBase64EncodedString:strEncodeData options:NSDataBase64DecodingIgnoreUnknownCharacters];
  return [UIImage imageWithData:data];
}

iOS 6.1 及 < 版本

第一个选项：使用此链接encode和decode图像

在你的project.

编码：

 NSData* data = UIImageJPEGRepresentation(yourImage, 1.0f);
 NSString *strEncoded = [Base64 encode:data];

解码：

 NSData* data = [Base64 decode:strEncoded ];;
 image.image = [UIImage imageWithData:data];

另一种选择：使用QSUtilities和encodingdecoding

于 2012-06-28T19:22:03.510 回答
67

斯威夫特 5

编码

func convertImageToBase64String (img: UIImage) -> String {
    return img.jpegData(compressionQuality: 1)?.base64EncodedString() ?? ""
}

解码

func convertBase64StringToImage (imageBase64String:String) -> UIImage {
    let imageData = Data(base64Encoded: imageBase64String)
    let image = UIImage(data: imageData!)
    return image!
}

注意：在 xcode 10.2 中测试

斯威夫特 4

编码

func convertImageToBase64String (img: UIImage) -> String {
    let imageData:NSData = UIImageJPEGRepresentation(img, 0.50)! as NSData //UIImagePNGRepresentation(img)
    let imgString = imageData.base64EncodedString(options: .init(rawValue: 0))
    return imgString
}

解码

func convertBase64StringToImage (imageBase64String:String) -> UIImage {
    let imageData = Data.init(base64Encoded: imageBase64String, options: .init(rawValue: 0))
    let image = UIImage(data: imageData!)
    return image
}

注意：在 xcode 9.4.1 中测试

于 2018-07-18T05:55:14.010 回答
41

Swift 4.2 扩展方法

extension UIImage {
    func toBase64() -> String? {
        guard let imageData = self.pngData() else { return nil }
        return imageData.base64EncodedString(options: .lineLength64Characters)
    }
}

XCode 9.1 和 Swift 4.0

//
// Convert UIImage to a base64 representation
//
class func convertImageToBase64(image: UIImage) -> String {
    let imageData = UIImagePNGRepresentation(image)!
    return imageData.base64EncodedString(options: Data.Base64EncodingOptions.lineLength64Characters)
}

//
// Convert a base64 representation to a UIImage
//
class func convertBase64ToImage(imageString: String) -> UIImage {
    let imageData = Data(base64Encoded: imageString, options: Data.Base64DecodingOptions.ignoreUnknownCharacters)!
    return UIImage(data: imageData)!
}
于 2017-12-02T17:48:30.980 回答
19

SWIFT 3.0、XCODE 8.0

将字符串替换为您的 URL。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

希望它有帮助谢谢。

于 2016-10-19T06:16:18.530 回答
11

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
于 2015-02-10T11:01:52.947 回答
8 
@implementation UIImage (Extended)

- (NSString *)base64String {
    NSData * data = [UIImagePNGRepresentation(self) base64EncodedDataWithOptions:NSDataBase64Encoding64CharacterLineLength];
    return [NSString stringWithUTF8String:[data bytes]];
}

@end
于 2013-10-02T15:17:16.923 回答
8

斯威夫特 3.0

将图像转换为 base64 字符串

在操场上测试

    var logo = UIImage(named: "image_logo")
    let imageData:Data =  UIImagePNGRepresentation(logo)
    let base64String = imageData.base64EncodedString()
    print(base64String)
于 2017-01-22T14:14:49.520 回答
7

在 swift 2.0 中使用这个扩展（感谢 Jonas Franz）

extension UIImage{
  func toBase64() -> String{
    let imageData = UIImagePNGRepresentation(self)!
    return imageData.base64EncodedStringWithOptions(.Encoding64CharacterLineLength)
  }
}
于 2015-10-23T17:33:23.450 回答
5

在 Swift 3.0 和 Xcode 8.0 中

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
于 2016-12-15T06:37:10.263 回答
4

快速扩展：

extension UIImage{
     func toBase64() -> String{
          var imageData = UIImagePNGRepresentation(self)
          return imageData.base64EncodedStringWithOptions(.allZeros)
     }
}
于 2015-07-02T15:38:11.053 回答
4

斯威夫特 4

enum ImageFormat {
    case png
    case jpeg(CGFloat)
}

extension UIImage {
    func base64(format: ImageFormat) -> String? {
        var imageData: Data?

        switch format {
        case .png: imageData = UIImagePNGRepresentation(self)
        case .jpeg(let compression): imageData = UIImageJPEGRepresentation(self, compression)
        }

        return imageData?.base64EncodedString()
    }
}

extension String {
    func imageFromBase64() -> UIImage? {
        guard let data = Data(base64Encoded: self) else { return nil }

        return UIImage(data: data)
    }
}
于 2018-11-21T20:00:04.017 回答
4

对于 Base64 代码，例如：

“数据：图像/ JPG; BASE64，iVBORw0KGgoAAAANSUhEUgAAAMgAAADIAQAAAACFI5MzAAAB9klEQVR42u2YQYorMQxEBbqWQFc36FoG / 6pyOpNZ / J20mGGaTiftF2hbLpWU2PnfYX / k55Jl5vhUVTu8luUdaCeFcydejjdwDUyQ5XV2JOcSZnkHZgiejusK51QGycrl2yIR1BwjjKivSFz8YC7fY91GKIj6PL5pp4 / wWL54t3MHt / AjFxoJwmkYwosbh6 / UEHE817hvi / vGex8gEkTdVRo1 / 55BM7kjUIgpoMW1DxB6kD + GtCX4PUFws40OwcUm0 / lRYjOB3pG9YcguBFQuO0ISJ9UIrUP5CKy / MriXHDkETYmLDax1 + RkgWBglQgUyq6T / HCAHBq7iJHd9KWWAlIKoGpiLc6HNDhDkETNYwqeVhym72snKKxA6BJL4UPM5QPYtgGwZeNZ5O0UvgSb0VGdcmVfJCQwQrM + pRiGnYJ497SUlv2NOYfOCX3qU2Equ7W3JAslsN7oDBDWWojcZq + KbEwQRdRYl1wD3ML52rpGc6w24qCXaKh4DRHWJbUPemqtEGyBMKC4Q / QmWiDWzRxkgO1UtSLh3svMaILeDpEGwrwvZ4Bkg9LynK1Y1LJWQdqKGnm3K7VTCz7vS9hIuUyYRd / xKcYRIHGqAViisQ4S / Uozmqo41Pn6bNRI1xS / fk2fMEKpDZYkpjP6B1T0HyN9 / Nb的+M/AORXDdE4Lb/mQAAAABJRU5ErkJggg==

使用 Swift5.0 代码，如：

func imageFromBase64(_ base64: String) -> UIImage? {
    if let url = URL(string: base64), let data = try? Data(contentsOf: url) {
        return UIImage(data: data)
    }
    return nil
}
于 2020-02-15T07:33:42.440 回答
3

斯威夫特 5。

class ImageConverter {

    func base64ToImage(_ base64String: String) -> UIImage? {
        guard let imageData = Data(base64Encoded: base64String) else { return nil }
        return UIImage(data: imageData)
    }

    func imageToBase64(_ image: UIImage) -> String? {
        return image.jpegData(compressionQuality: 1)?.base64EncodedString()
    }

}
于 2019-09-02T13:17:49.773 回答
2

Swift 版本 - 为图像创建 base64

在我看来，在不安全的情况下隐式展开可选UIImagePNGRepresenatation()是不安全的，所以我建议使用如下扩展：

extension UIImage {

    func toBase64() -> String? {
        let imageData = UIImagePNGRepresentation(self)
        return imageData?.base64EncodedStringWithOptions(NSDataBase64EncodingOptions.Encoding64CharacterLineLength)
    }
}
于 2016-09-07T13:46:41.753 回答
2

我尝试了所有解决方案，但没有一个对我有用（使用 Swift 4），如果将来有人遇到同样的问题，这是对我有用的解决方案。

let temp = base64String.components(separatedBy: ",")
let dataDecoded : Data = Data(base64Encoded: temp[1], options: 
 .ignoreUnknownCharacters)!
let decodedimage = UIImage(data: dataDecoded)

yourImage.image = decodedimage
于 2018-07-19T15:51:36.397 回答
2

正如Tyler Sheaffer所说，您是否通过前缀非常好理解。但由于某种原因，您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
    }
}
于 2020-03-11T09:35:53.267 回答
2

使用便利初始化程序解码 - Swift 5

extension UIImage {
    convenience init?(base64String: String) {
        guard let data = Data(base64Encoded: base64String) else { return nil }
        self.init(data: data)
    }
}
于 2020-07-23T17:09:08.100 回答
1 
See my class -  AppExtension.swift


// MARK: - UIImage (Base64 Encoding)

public enum ImageFormat {
    case PNG
    case JPEG(CGFloat)
}

extension UIImage {

    public func base64(format: ImageFormat) -> String {
        var imageData: NSData
        switch format {
        case .PNG: imageData = UIImagePNGRepresentation(self)
        case .JPEG(let compression): imageData = UIImageJPEGRepresentation(self, compression)
        }
        return imageData.base64EncodedStringWithOptions(.allZeros)
    }
}
于 2015-10-13T08:47:27.733 回答
1

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!

}
于 2016-10-19T14:01:59.753 回答
1

斯威夫特 4.2 | Xcode 10

extension UIImage {

    /// EZSE: Returns base64 string
    public var base64: String {
        return self.jpegData(compressionQuality: 1.0)!.base64EncodedString()
    }
}
于 2018-10-05T13:03:58.400 回答
1

斯威夫特 5，Xcode 10。

 let imageData = UIImage(named:"imagename").pngData()?.base64EncodedString(options: .lineLength64Characters)

print(imageData)

于 2018-12-13T08:45:00.597 回答
1 
//convert Image to Base64 (Encoding)

let strBase64 = imageData.base64EncodedString(options: .lineLength64Characters)

print(strBase64)

// convert Base64 to Image (Decoding)

let dataDecoded:NSData = NSData(base64EncodedString: strBase64, options: NSDataBase64DecodingOptions(rawValue: 0))!

let decodedimage:UIImage = UIImage(data: dataDecoded)!

print(decodedimage)

yourImageView.image = decodedimage
于 2019-10-05T06:49:34.793 回答
0

对于 iOS 7+，Objective-C，以下是从图像 URL 开始进行转换的方法：

NSURL *url = [NSURL URLWithString:self.groove.thumbnailURL];

UIImage *image = [UIImage imageWithData:[NSData dataWithContentsOfURL:url]];

NSString *base64String = [UIImagePNGRepresentation(image)
base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
于 2014-12-24T00:50:48.033 回答
0

斯威夫特 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)
于 2017-01-09T11:20:55.297 回答