ios - 如何在 swift 3 中使用现有的 SQLite？ (FMDB)

Question

我想将 (Salary.db) 连接到我的 iOS (Swift) 项目并从数据库中获取数据？

第一步，如何在 Swift 3 中连接现有数据库？

let fileURL = try! FileManager.default
            .url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
            .appendingPathComponent("Salary.db")

guard let database = FMDatabase(path: fileURL.path) else {
    print("unable to create database")
    return
}

guard database.open() else {
    print("Unable to open database")
    return
}

Answer 1

FMDB 是一个很棒的 Objective-C 库，尚未针对 Swift 进行更新，有时在 Swift 中感觉很别扭。

您可以考虑使用像 GRDB.swift 这样的库这是用 Swift 编写的，健壮的，fast ，并授予您与 FMDB 相同的功能:

import GRDB

// GRDB's DatabaseQueue is similar to FMDB's FMDatabaseQueue
let dbQueue = try DatabaseQueue(path: "/path/to/database.sqlite")

try dbQueue.inDatabase { db in
    // Same as FMDB's -[FMDatabase executeUpdate:withArgumentsInArray:]
    try db.execute(
        "INSERT INTO pointOfInterests (title, favorite, latitude, longitude) " +
        "VALUES (?, ?, ?, ?)",
        arguments: ["Paris", true, 48.85341, 2.3488])

    // Same as FMDB's -[FMDatabase executeQuery:] and FMResultSet
    let rows = try Row.fetchCursor(db, "SELECT * FROM pointOfInterests")
    while let row = try rows.next() {
        let title: String = row.value(named: "title")
        let isFavorite: Bool = row.value(named: "favorite")
        let coordinate = CLLocationCoordinate2DMake(
            row.value(named: "latitude"),
            row.value(named: "longitude"))
    }
}

GRDB 还允许您在不需要时避免编写 SQL。查看README.md获取更多信息。