获取内置SD卡很简单，就一行代码

/**

* 获取内置SD卡路径

* @return

*/

public String getInnerSDCardPath() {

return Environment.getExternalStorageDirectory().getPath();

}

获取外置SD卡比较麻烦，

/**

* 获取外置SD卡路径

* @return

*/

public List getExtSDCardPaths() {

List paths = new ArrayList();

String extFileStatus = Environment.getExternalStorageState();

File extFile = Environment.getExternalStorageDirectory();

if (extFileStatus.endsWith(Environment.MEDIA_UNMOUNTED)

&& extFile.exists() && extFile.isDirectory()

&& extFile.canWrite()) {

paths.add(extFile.getAbsolutePath());

}

try {

// obtain executed result of command line code of 'mount', to judge

// whether tfCard exists by the result

Runtime runtime = Runtime.getRuntime();

Process process = runtime.exec("mount");

InputStream is = process.getInputStream();

InputStreamReader isr = new InputStreamReader(is);

BufferedReader br = new BufferedReader(isr);

String line = null;

int mountPathIndex = 1;

while ((line = br.readLine()) != null) {

if ((!line.contains("fat") && !line.contains("fuse") && !line

.contains("storage"))

|| line.contains("secure")

|| line.contains("asec")

|| line.contains("firmware")

|| line.contains("shell")

|| line.contains("obb")

|| line.contains("legacy") || line.contains("data")) {

continue;

}

String[] parts = line.split(" ");

int length = parts.length;

if (mountPathIndex >= length) {

continue;

}

String mountPath = parts[mountPathIndex];

if (!mountPath.contains("/") || mountPath.contains("data")

|| mountPath.contains("Data")) {

continue;

}

File mountRoot = new File(mountPath);

if (!mountRoot.exists() || !mountRoot.isDirectory()

|| !mountRoot.canWrite()) {

continue;

}

boolean equalsToPrimarySD = mountPath.equals(extFile

.getAbsolutePath());

if (equalsToPrimarySD) {

continue;

}

paths.add(mountPath);

}

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return paths;

}

首先获取了Android标准一部分的外置SD卡，如果它可用的话。

然后利用运行时，通过命令行函数"mount"来获取所有的存储位置，并对返回的结果进行SD卡或者TF卡的查找。

最后返回了所有可用于存储的不同的卡的位置，用一个List来保存。由于不是所有的手机都支持TF卡，因而这个List包含的路径未必很多，只有一个SD卡的手机只会返回一个路径，多个可用存储位置的会返回多个路径。

但有一点，是必须的，paths.get(0)肯定是外置SD卡的位置，因为它是primary external storage.