将ArrayLists保存在SQLite数据库中 [英] Saving ArrayLists in SQLite databases

问题描述

所以我想保存一组有序的double值，我想能够轻松地插入，检索或删除任何值。这样，我使用一个ArrayList，在那里我定义一个名为Doubles的类来存储双精度值。

So I want to save an ordered set of double values, and I want to be able to insert, retrieve or delete any value from this easily. As of such, I'm using a an ArrayList, where I define a class called Doubles to store the double values.

如何将此数组列表存储在记录中一个SQLite数据库？我的意思是...柱类型应该是什么？可以做吗？

How do I store this arraylist in a record in an SQLite database? I mean...what should the columns type be? Can it be done?

推荐答案

不能将ArrayList直接插入Sqlite。相反，你可以使用JSONObject（org.json.JSONObject）来插入ArrayList。请检查下面的代码段，您可以尝试下面的内容....

You cannot insert ArrayList directly into Sqlite. Instead, you could use JSONObject (org.json.JSONObject) to insert the ArrayList. Please check below snippet, you can try something like below....

要插入

JSONObject json = new JSONObject();
json.put("uniqueArrays", new JSONArray(items));
String arrayList = json.toString();

将字符串插入db。

阅读，
从db中读取字符串作为String，

To Read, Read the string from db as String,

 JSONObject json = new JSONObject(stringreadfromsqlite);
  ArrayList items = json.optJSONArray("uniqueArrays");

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