1 package com.zyh.sdcardHelper;
2
3 import java.io.BufferedInputStream;
4 import java.io.BufferedOutputStream;
5 import java.io.ByteArrayOutputStream;
6 import java.io.File;
7 import java.io.FileInputStream;
8 import java.io.FileOutputStream;
9 import java.io.IOException;
10
11 import android.content.Context;
12 import android.graphics.Bitmap;
13 import android.graphics.BitmapFactory;
14 import android.os.Environment;
15 import android.os.StatFs;
16 import android.text.format.Formatter;
17
18 public class SDCardHelper {
19 //判断SD卡是否被挂载
20 public static boolean isSDCardMounted(){
21 return Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED);
22 }
23
24 //获取SDCard的绝对路径目录
25 public static String getSDCardBaseDir(){
26 if(isSDCardMounted()){
27 return Environment.getExternalStorageDirectory().getAbsolutePath();
28 }
29 return null;
30 }
31
32 //获取SDCard总大小
33 public static String getSDCardTotalSize(Context context){
34 if(isSDCardMounted()){
35 StatFs fs = new StatFs(getSDCardBaseDir());
36 long blockSize = fs.getBlockSize();
37 long totalBlocks = fs.getBlockCount();
38 long totalSize = blockSize * totalBlocks;
39 return Formatter.formatFileSize(context, totalSize);
40 }
41 return null;
42 }
43
44 //获取sd卡的剩余空间
45 public static String getSDCardFreeSize(Context context){
46 if(isSDCardMounted()){
47 StatFs fs = new StatFs(getSDCardBaseDir());
48 long blockSize = fs.getBlockSize();
49 long freeBlocks = fs.getFreeBlocks();
50 long freeSize = blockSize * freeBlocks;
51 return Formatter.formatFileSize(context, freeSize);
52 }
53 return null;
54 }
55
56 //获取sd卡的可用空间
57 public static String getSDCardAvailableSize(Context context){
58 if(isSDCardMounted()){
59 StatFs fs = new StatFs(getSDCardBaseDir());
60 long blockSize = fs.getBlockSize();
61 long availableBlocks = fs.getFreeBlocks();
62 long availableSize = blockSize * availableBlocks;
63 return Formatter.formatFileSize(context, availableSize);
64 }
65 return null;
66 }
67
68 //往sd卡的公有目录下保存数据进文件
69 public static boolean saveFileToSDCardPublicDir(byte[] data, String type, String fileName){
70 BufferedOutputStream bos = null;
71 if(isSDCardMounted()){
72 try {
73 File file = Environment.getExternalStoragePublicDirectory(type);
74 bos = new BufferedOutputStream(new FileOutputStream(new File(file,fileName)));
75 bos.write(data);
76 bos.flush();
77 return true;
78 } catch (Exception e) {
79 // TODO Auto-generated catch block
80 e.printStackTrace();
81 }finally{
82 try {
83 bos.close();
84 } catch (IOException e) {
85 // TODO Auto-generated catch block
86 e.printStackTrace();
87 }
88 }
89 }
90 return false;
91 }
92
93 //往sd卡用户自定义目录中保存数据进文件
94 public static boolean savaFileToSDCardCustomDir(byte[] data, String dir, String fileName){
95 BufferedOutputStream bos = null;
96 if(isSDCardMounted()){
97 try {
98 File file = new File(getSDCardBaseDir() + File.separator + dir);
99 if(!file.exists()){
100 file.mkdirs();//递归创建自定义目录
101 }
102 bos = new BufferedOutputStream(new FileOutputStream(new File(file,fileName)));
103 bos.write(data);
104 bos.flush();
105 return true;
106 } catch (Exception e) {
107 // TODO Auto-generated catch block
108 e.printStackTrace();
109 }finally{
110 try {
111 bos.close();
112 } catch (IOException e) {
113 // TODO Auto-generated catch block
114 e.printStackTrace();
115 }
116 }
117 }
118 return false;
119 }
120
121 //往sd卡私有Files目录下保存数据进文件
122 //注意如果不加<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>这个权限，则报空指针异常
123 //type可用为null
124 public static boolean saveFileToSDCardPrivateFilesDir(byte[] data, String type, String fileName, Context context){
125 BufferedOutputStream bos = null;
126 if(isSDCardMounted()){
127 try {
128 File file = context.getExternalFilesDir(type);
129 bos = new BufferedOutputStream(new FileOutputStream(new File(file,fileName)));
130 bos.write(data);
131 bos.flush();
132 return true;
133 } catch (Exception e) {
134 // TODO Auto-generated catch block
135 e.printStackTrace();
136 }finally{
137 try {
138 bos.close();
139 } catch (IOException e) {
140 // TODO Auto-generated catch block
141 e.printStackTrace();
142 }
143 }
144 }
145 return false;
146 }
147
148 //往sd卡的私有Cache目录下保存数据进文件
149 //cache目录和files目录是同一级的
150 public static boolean saveFileToSDCardPrivateCacheDir(byte[] data, String fileName, Context context){
151 BufferedOutputStream bos = null;
152 if(isSDCardMounted()){
153 try {
154 File file = context.getExternalCacheDir();
155 bos = new BufferedOutputStream(new FileOutputStream(new File(file,fileName)));
156 bos.write(data);
157 bos.flush();
158 return true;
159 } catch (Exception e) {
160 // TODO Auto-generated catch block
161 e.printStackTrace();
162 }finally{
163 try {
164 bos.close();
165 } catch (IOException e) {
166 // TODO Auto-generated catch block
167 e.printStackTrace();
168 }
169 }
170 }
171 return false;
172 }
173
174 //把bitmap保存在sd卡的私有cache目录中
175 public static boolean saveBitmapToSDCardPrivateCacheDir(Bitmap bitmap,String fileName, Context context){
176 if(isSDCardMounted()){
177 BufferedOutputStream bos = null;
178 File file = context.getExternalCacheDir();
179 try {
180 bos = new BufferedOutputStream(new FileOutputStream(new File(file,fileName)));
181 //100表示压缩率为0
182 if(fileName != null && (fileName.endsWith(".png") || fileName.endsWith(".PNG"))){
183 bitmap.compress(Bitmap.CompressFormat.PNG, 100, bos);
184 }else{
185 bitmap.compress(Bitmap.CompressFormat.JPEG, 100, bos);
186 }
187 bos.flush();
188 } catch (Exception e) {
189 // TODO Auto-generated catch block
190 e.printStackTrace();
191 }finally{
192 if(bos != null){
193 try {
194 bos.close();
195 } catch (IOException e) {
196 // TODO Auto-generated catch block
197 e.printStackTrace();
198 }
199 }
200 }
201 return true;
202 }
203 return false;
204 }
205
206 //从sd卡的路径中获取文件的内容
207 public static byte[] readFileFromSDCard(String filePath){
208 BufferedInputStream bis = null;
209 ByteArrayOutputStream baos = new ByteArrayOutputStream();
210 try {
211 bis = new BufferedInputStream(new FileInputStream(new File(filePath)));
212 byte[] buffer = new byte[8 * 1024];
213 int hasRead = 0;
214 while((hasRead = bis.read(buffer)) != -1){
215 baos.write(buffer, 0, hasRead);
216 baos.flush();
217 }
218 return baos.toByteArray();
219 } catch (Exception e) {
220 // TODO Auto-generated catch block
221 e.printStackTrace();
222 }finally{
223 try {
224 baos.close();
225 bis.close();
226 } catch (IOException e) {
227 // TODO Auto-generated catch block
228 e.printStackTrace();
229 }
230 }
231 return null;
232 }
233
234 //从sd卡中获取Bitmap文件
235 public static Bitmap loadBitmapFromSDCard(String filePath){
236 byte[] data = readFileFromSDCard(filePath);
237 if(data != null){
238 Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
239 if(bitmap != null){
240 return bitmap;
241 }
242 }
243 return null;
244 }
245
246 //获取sd卡的公有目录路径
247 public static String getSDCardPublicDir(String type){
248 return Environment.getExternalStoragePublicDirectory(type).toString();
249
250 }
251
252 //获取sd卡私有cache目录路径
253 public static String getSDCardPrivateCacheDir(Context context){
254 return context.getExternalCacheDir().getAbsolutePath();
255 }
256
257 //sd卡私有files目录下的路径
258 public static String getSDCardPrivateFilesDir(Context context, String type){
259 return context.getExternalFilesDir(type).getAbsolutePath();
260 }
261
262 //从sd卡中删除文件
263 public static boolean removeFileFromSDCard(String filePath){
264 File file = new File(filePath);
265 if(file.exists()){
266 try {
267 file.delete();
268 return true;
269 } catch (Exception e) {
270 return false;
271 }
272 }
273 return false;
274 }
275
276 }
参考:http://www.androidchina.net/4106.html
时间： 2024-10-11 14:49:27