- 引入 log 庫(kù)
- 自定義log 類(lèi)型，便于搜索藻丢，一般般包名和模塊
// Add logging to your app in three simple steps
import os
let logger = Logger(subsystem: "com.example.Fruta", category: "giftcards")
func beginTask(url: URL, handler: (Data) -> Void) {
launchTask(with: url) {
handler($0)
}
logger.log("Started a task")
}
public
logger.log("Ordered smoothie \(smoothieName, privacy: .public)")
格式化
logger.log("\(data, format: .hex, align: .right(columns: width))")
import SwiftUI
import os
let statisticsLogger = Logger(subsystem: "com.example.Fruta", category: "statistics")
// Log statistics about communication with a server.
func logStatistics(taskID: UUID, giftCardID: String, serverID: Int, seconds: Double) {
statisticsLogger.log("\(taskID) \(giftCardID, align: .left(columns: GiftCard.maxIDLength)) \(serverID) \(seconds, format: .fixed(precision: 2))")
}
