ios - 如何将 svg+xml base64 转换为 UIImage？

Question

我只是有这样的字符串：

"data:image/svg+xml;base64,PHN2ZyB3aWR0aD0iNDAwIiBoZWlnaHQ9IjYwMCIgeG1sbnM9Imh0dHA6Ly93d3cudzMub3JnLzIwMDAvc3ZnIiB4bWxuczp4bGluaz0iaHR0cDovL3d3dy53My5vcmcvMTk5OS94bGluayI+CgogPGc+CiAgPHRpdGxlPkxheWVyIDE8L3RpdGxlPgogIDxwYXRoIGlkPSJzdmdfMSIgc3Ryb2tlPSIjMDAwIiBmaWxsPSIjZmZmIi8+CiAgPHJlY3Qgcng9IjYyIiBzdHJva2Utd2lkdGg9IjEwIiBpZD0ic3ZnXzIiIGhlaWdodD0iMzAzIiB3aWR0aD0iNjI5IiB5PSIxMTIiIHg9IjkxIiBzdHJva2U9IiMwMDAiIGZpbGw9IiNmZmYiLz4KICA8ZGVmcz4KICA8cmVjdCByeT0iNjMiIHJ4PSI2MyIgc3Ryb2tlLXdpZHRoPSIxMCIgaWQ9InJlY3QiIGhlaWdodD0iMTI2IiB3aWR0aD0iMTI2IiB5PSIxNTAiIHg9IjE0MCIgc3Ryb2tlPSIjMDAwIiBmaWxsPSIjZmZmIi8+CiAgPGNsaXBQYXRoIGlkPSJjbGlwIj4KICAgICAgPHVzZSB4bGluazpocmVmPSIjcmVjdCIvPgogICAgPC9jbGlwUGF0aD4KPC9kZWZzPgoKICA8dXNlIHhsaW5rOmhyZWY9IiNyZWN0IiBzdHJva2Utd2lkdGg9IjIiIHN0cm9rZT0iYmxhY2siLz4KICA8aW1hZ2UgeGxpbms6aHJlZj0iZGF0YTppbWFnZS9wbmc7YmFzZTY0LGlWQk9SdzBLR2dvQUFBQU5TVWhFVWdBQUFHUUFBQUJrQ0FJQUFBRC9nQUlEQUFBRENrbEVRVlI0bk95ZFhVaFRjUnlHZC9SUUpFSE1WU3BwdFJiWWwwWWZHcWxZTVNnS2pNZ1V2SWt5R3RLY2RKZkVvckpGUVlyV3hReGNRUVcxQzhHaE80WE1ncUNJRWxtME1ZTkZ3VENFR3BSRk9jaWllOEVYM3Z2M3VYM1lPRHo4THM2Qi8va2QwNUdldFMxTUpERUI3RlQ0TTdDMWxoMVlZNkFOMkZ1aExMQ1B5bnFBUFhiMU1MQ2w2OUJ2dTE5ZkF6WVBPREVQeFNKUUxBTEZJbEFzQXNVaVVDd0N4U0pRTEFKejZWY1Q2TWtYZm1BYk8xY0JHNjFZQVd5aXJSN1l2dXFMd0s3SlRRRTduZDRQN0pleE9MQ0ZSY2VCMVdRUktCYUJZaEVvRm9GaUVTZ1dnV0lSS0JhQlloR1lXNWNiUUR2dHU0RDFqZXdEZHMvWlA4Q1d1SXVBdlRsVEJ1eUE3eVN3VnFRZjJPR0NsY0F1c3lXQTFXUVJLQmFCWWhFb0ZvRmlFU2dXZ1dJUktCYUJZaEdZUXpjK0FqMmJPd2RzUjBzcHNET2JEZ0o3enhVR2RuaXpHOWdsK2FlQWRlU2paNUx5WURHd3llYTd3R3F5Q0JTTFFMRUlGSXRBc1FnVWkwQ3hDQlNMUUxFSXpPTFlKNkNUbFU1Z2ExNjlBL2IzNmc1Z2I5dlBBMXUrRzkyRkY0NC9BN1lsTUFoc3dJbm1JNXhCWjJ3MFdRU0tSYUJZQklwRm9GZ0Vpa1dnV0FTS1JhQllCRVpYNmkzUU93TG9qdlpJNndmMDMyUG90UHJjNDFGZzMzaEhnTTAyUGdIMlVud2pzTDJIMERWWDJaSFZaQkVvRm9GaUVTZ1dnV0lSS0JhQlloRW9Gb0ZpRVJqcEp2VGVaMmNFdlcvNnZtRVJzTk1KZEtiOHg0TmVZUE1HMFlhY254UGJnYTNMZEFQYjAzNEMyQzAxZTlGVkFTZm1vVmdFaWtXZ1dBU0tSYUJZQklwRm9GZ0Vpa1ZndEhxalFLZlFvaHJiL2ZwSllFYzlCNEIxUjBQQTlnODFBN3Y0NzNWZy9hZVBBcnZUampaZ1B1eERwNFkwV1FTS1JhQllCSXBGb0ZnRWlrV2dXQVNLUmFCWUJFWW02UVg2elBNVXNITU5QbURqbmlwZ3ZlMXJnYlVLU29EMVAwVjdLaS9IcW9FTlhrRDdNYk5KQzFoTkZvRmlFU2dXZ1dJUktCYUJZaEVvRm9GaUVTZ1dnZWtJTlFFZGZPa0M5b3BaQit6M0N2UjFwRzIxNkp0TnY2dzd3RlorV3cvc1A5ODRzQnM4WGNER1hEbGdOVmtFaWtXZ1dBU0tSYUJZQklwRm9GZ0Vpa1dnV0FUL0F3QUEvLy9yWFpLVzhmMG5SQUFBQUFCSlJVNUVya0pnZ2c9PSIgd2lkdGg9IjEwMCIgaGVpZ2h0PSIxMDAiIHk9IjE2MCIgeD0iMTYwIiBjbGlwLXBhdGg9InVybCgjY2xpcCkiLz4KCiAgPHRleHQgeG1sOnNwYWNlPSJwcmVzZXJ2ZSIgdGV4dC1hbmNob3I9InN0YXJ0IiBmb250LWZhbWlseT0iTm90byBTYW5zIEpQIiBmb250LXNpemU9IjI0IiBpZD0ic3ZnXzQiIHk9IjM0MiIgeD0iMTc5IiBzdHJva2Utd2lkdGg9IjAiIHN0cm9rZT0iIzAwMCIgZmlsbD0iIzAwMDAwMCI+YXNnZGhqYWdhc2Rqa2FzZGg8L3RleHQ+CiAgPHRleHQgdHJhbnNmb3JtPSJtYXRyaXgoMTguMDU3LCAwLCAwLCA3LjM3MzIsIC04NDI5LjI0LCAtMTkxNS40NSkiIHhtbDpzcGFjZT0icHJlc2VydmUiIHRleHQtYW5jaG9yPSJzdGFydCIgZm9udC1mYW1pbHk9IidEYW5jaW5nIFNjcmlwdCciIGZvbnQtc2l6ZT0iMSIgaWQ9InN2Z183IiB5PSIyOTAuNTEwNjEiIHg9IjQ5Ny4wODEyNyIgc3Ryb2tlLXdpZHRoPSI4IiBzdHJva2U9IiMwMDAiIGZpbGw9IiNmZmYiPmU8L3RleHQ+CiA8L2c+Cjwvc3ZnPg=="

如何使用SVGKit cocoapod 库将其转换为 UIImage？

现在我只是使用：

var image: UIImage? {
    guard let imageEncodedString = imageEncodedString else {
        return nil
    }
    return SVGKImage(data: Data(base64Encoded: imageEncodedString))?.uiImage //crash here inside init
}

Answer 1

字符串的开头不是base64，这就是它失败的原因。您需要先删除data:image/svg+xml;base64,.

你有一个数据 URI。

它应该是这样的：

data:[<media type>][;base64],<data>

您目前拥有：

data:image/svg+xml;base64,theBase64Image

现在，您可以始终data:image/svg+xml;base64,从字符串中删除：

let dataURI = "data:image/svg+xml;base64,theBase64Image"
let base64String = dataURI.replacingOccurrences(of: "data:image/svg+xml;base64,", with: "")

您还可以事先检查hasPrefix()以确保它具有预期的 dataURI。您也可以使用 Regex NSScanner、 等来执行此操作。

但是，既然您期望 SVG 在 base64 中，hasPrefix()应该replacingOccurrences(of:with:)就足够了。