虽然您可能应该使用许多SQLite包装器之一，但如果您想知道如何自己调用SQLite库，则可以：
配置您的Swift项目以处理SQLite C调用。如果使用Xpre 9或更高版本，则只需执行以下操作：
import SQLite3
创建/打开数据库。
let fileURL = try! FileManager.default .url(for: .applicationSupportDirectory, in: .userDomainMask, appropriateFor: nil, create: true) .appendingPathComponent("test.sqlite") // open database var db: OpaquePointer? guard sqlite3_open(fileURL.path, &db) == SQLITE_OK else { print("error opening database") sqlite3_close(db) db = nil return }注意，我知道在打开失败后关闭数据库似乎很奇怪，但是
sqlite3_open
文档明确指出我们必须这样做以避免内存泄漏：
无论错误是否在打开时发生，与数据库连接句柄关联的资源都应通过将其传递给
sqlite3_close()不再需要时释放。
- 使用
sqlite3_exec
执行SQL（如创建表）。
if sqlite3_exec(db, "create table if not exists test (id integer primary key autoincrement, name text)", nil, nil, nil) != SQLITE_OK { let errmsg = String(cString: sqlite3_errmsg(db)!) print("error creating table: (errmsg)") }- 使用
sqlite3_prepare_v2
与准备SQL?
，这是我们将绑定值的占位符。
var statement: OpaquePointer? if sqlite3_prepare_v2(db, "insert into test (name) values (?)", -1, &statement, nil) != SQLITE_OK { let errmsg = String(cString: sqlite3_errmsg(db)!) print("error preparing insert: (errmsg)") } if sqlite3_bind_text(statement, 1, "foo", -1, SQLITE_TRANSIENT) != SQLITE_OK { let errmsg = String(cString: sqlite3_errmsg(db)!) print("failure binding foo: (errmsg)") } if sqlite3_step(statement) != SQLITE_DONE { let errmsg = String(cString: sqlite3_errmsg(db)!) print("failure inserting foo: (errmsg)") }注意，它使用可以如下实现的
SQLITE_TRANSIENT常量：
internal let SQLITE_STATIC = unsafeBitCast(0, to: sqlite3_destructor_type.self) internal let SQLITE_TRANSIENT = unsafeBitCast(-1, to: sqlite3_destructor_type.self)
- 重置SQL以插入另一个值。在此示例中，我将插入一个
NULL
值：
if sqlite3_reset(statement) != SQLITE_OK { let errmsg = String(cString: sqlite3_errmsg(db)!) print("error resetting prepared statement: (errmsg)") } if sqlite3_bind_null(statement, 1) != SQLITE_OK { let errmsg = String(cString: sqlite3_errmsg(db)!) print("failure binding null: (errmsg)") } if sqlite3_step(statement) != SQLITE_DONE { let errmsg = String(cString: sqlite3_errmsg(db)!) print("failure inserting null: (errmsg)") }- 完成准备好的语句以恢复与该准备好的语句关联的内存：
if sqlite3_finalize(statement) != SQLITE_OK { let errmsg = String(cString: sqlite3_errmsg(db)!) print("error finalizing prepared statement: (errmsg)") } statement = nil- 准备用于从表中选择值的新语句，并通过检索值循环：
if sqlite3_prepare_v2(db, "select id, name from test", -1, &statement, nil) != SQLITE_OK { let errmsg = String(cString: sqlite3_errmsg(db)!) print("error preparing select: (errmsg)") } while sqlite3_step(statement) == SQLITE_ROW { let id = sqlite3_column_int64(statement, 0) print("id = (id); ", terminator: "") if let cString = sqlite3_column_text(statement, 1) { let name = String(cString: cString) print("name = (name)") } else { print("name not found") } } if sqlite3_finalize(statement) != SQLITE_OK { let errmsg = String(cString: sqlite3_errmsg(db)!) print("error finalizing prepared statement: (errmsg)") } statement = nil- 关闭数据库：
if sqlite3_close(db) != SQLITE_OK { print("error closing database") } db = nil
