【Android Studio】安卓APP期末作品记录之连接sqlite数据库以及简单的sqlite增删改查

import android.content.ContentValues
import android.content.Context
import android.database.sqlite.SQLiteDatabase
import android.database.sqlite.SQLiteOpenHelper
 
class DatabaseHelper(context: Context) : SQLiteOpenHelper(context, "Student.db", null, 1) {
 
    override fun onCreate(db: SQLiteDatabase) {
        val createTableStatement = "CREATE TABLE Student (ID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT, AGE INTEGER, GENDER TEXT)"
        db.execSQL(createTableStatement)
    }
 
    override fun onUpgrade(db: SQLiteDatabase, oldVersion: Int, newVersion: Int) {
        val dropTableStatement = "DROP TABLE IF EXISTS Student"
        db.execSQL(dropTableStatement)
        onCreate(db)
    }
 
    fun insertData(name: String, age: Int, gender: String): Long {
        val db = this.writableDatabase
        val contentValues = ContentValues()
        contentValues.put("NAME", name)
        contentValues.put("AGE", age)
        contentValues.put("GENDER", gender)
        val rowID = db.insert("Student", null, contentValues)
        db.close()
        return rowID
    }
 
    fun deleteData(id: Int): Int {
        val db = this.writableDatabase
        val deleteQuery = "DELETE FROM Student WHERE ID = ?"
        val deletedRows = db.delete("Student", "ID = ?", arrayOf(id.toString()))
        db.close()
        return deletedRows
    }
}

这段代码定义了一个DatabaseHelper类，继承自SQLiteOpenHelper。在onCreate方法中创建了一个名为Student的表，包含ID、NAME、AGE和GENDER四个字段。onUpgrade方法用于在数据库版本更新时，删除旧表并重新创建。insertData方法用于插入学生信息，而deleteData方法用于删除指定ID的学生信息。这些方法都通过ContentValues进行数据的插入和删除操作。