Android SharedPreferences保存和读取对象 _references

一年好景君须记，最是橙黄橘绿时。这篇文章主要讲述Android SharedPreferences保存和读取对象相关的知识，希望能为你提供帮助。
【Android SharedPreferences保存和读取对象】SharedPreferences保存和读取对象

1.首先要序列化对象(以下是序列化实体类的样例，不方便贴出实体类全部的代码)

public class LoginResult extends BaseResult implements Serializable{ private static final long serialVersionUID = 1L; private String mobiletoken;

2.保存和读取对象的封装

public class ObjectSaveUtil { private final static String FILENAME = " login_data_save" ; private final static String KEY = " loginResult" ; /** * desc:保存对象 * @param context * @param key * @param obj 要保存的对象，仅仅能保存实现了serializable的对象 * modified: */ public static void saveObject(Context context,Object obj){ try { // 保存对象 SharedPreferences.Editor sharedata = https://www.songbingjia.com/android/context.getSharedPreferences(FILENAME, 0).edit(); //先将序列化结果写到byte缓存中，事实上就分配一个内存空间 ByteArrayOutputStream bos=new ByteArrayOutputStream(); ObjectOutputStream os=new ObjectOutputStream(bos); //将对象序列化写入byte缓存 os.writeObject(obj); //将序列化的数据转为16进制保存 String bytesToHexString = bytesToHexString(bos.toByteArray()); //保存该16进制数组 sharedata.putString(KEY, bytesToHexString); sharedata.commit(); } catch (IOException e) { e.printStackTrace(); Log.e(" " , " 保存obj失败" ); } } /** * desc:将数组转为16进制 * @param bArray * @return * modified: */ public static String bytesToHexString(byte[] bArray) { if(bArray == null){ return null; } if(bArray.length == 0){ return " " ; } StringBuffer sb = new StringBuffer(bArray.length); String sTemp; for (int i = 0; i < bArray.length; i++) { sTemp = Integer.toHexString(0xFF & bArray[i]); if (sTemp.length() < 2) sb.append(0); sb.append(sTemp.toUpperCase()); } return sb.toString(); } /** * desc:获取保存的Object对象 * @param context * @param key * @return * modified: */ public static Object readObject(Context context){ try { SharedPreferences sharedata = context.getSharedPreferences(FILENAME, 0); if (sharedata.contains(KEY)) { String string = sharedata.getString(KEY, " " ); if(TextUtils.isEmpty(string)){ return null; }else{ //将16进制的数据转为数组。准备反序列化 byte[] stringToBytes = StringToBytes(string); ByteArrayInputStream bis=new ByteArrayInputStream(stringToBytes); ObjectInputStream is=new ObjectInputStream(bis); //返回反序列化得到的对象 Object readObject = is.readObject(); return readObject; } } } catch (StreamCorruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } //全部异常返回null return null; } /** * desc:将16进制的数据转为数组 * < p> 创建人：聂旭阳 , 2014-5-25 上午11:08:33< /p> * @param data * @return * modified: */ public static byte[] StringToBytes(String data){ String hexString=data.toUpperCase().trim(); if (hexString.length()%2!=0) { return null; } byte[] retData=new byte[hexString.length()/2]; for(int i=0; i< hexString.length(); i++) { int int_ch; // 两位16进制数转化后的10进制数 char hex_char1 = hexString.charAt(i); ////两位16进制数中的第一位(高位*16) int int_ch3; if(hex_char1 > = ' 0' & & hex_char1 < =' 9' ) int_ch3 = (hex_char1-48)*16; //// 0 的Ascll - 48 else if(hex_char1 > = ' A' & & hex_char1 < =' F' ) int_ch3 = (hex_char1-55)*16; //// A 的Ascll - 65 else return null; i++; char hex_char2 = hexString.charAt(i); ///两位16进制数中的第二位(低位) int int_ch4; if(hex_char2 > = ' 0' & & hex_char2 < =' 9' ) int_ch4 = (hex_char2-48); //// 0 的Ascll - 48 else if(hex_char2 > = ' A' & & hex_char2 < =' F' ) int_ch4 = hex_char2-55; //// A 的Ascll - 65 else return null; int_ch = int_ch3+int_ch4; retData[i/2]=(byte) int_ch; //将转化后的数放入Byte里 } return retData; } }

挺好用的，欢迎大家复制使用