获取SdCard和系统存储空间大小

/**
* 读取Sd卡存储信息
*/
void readSDCard() {
		String state = Environment.getExternalStorageState();
		if (Environment.MEDIA_MOUNTED.equals(state)) {
			File sdcardDir = Environment.getExternalStorageDirectory();
			StatFs sf = new StatFs(sdcardDir.getPath());
			long blockSize = sf.getBlockSize();
			long blockCount = sf.getBlockCount();
			long availCount = sf.getAvailableBlocks();
			System.out.println("Sd card Total Space:" + blockSize * blockCount / 1024/1024 + "M");
			System.out.println("Sd card Remain Space:" + availCount * blockSize / 1024/1024 + "M");
		}
	}

/**
* 读取系统存储信息
*/
void readSystem() {
		File root = Environment.getRootDirectory();
		StatFs sf = new StatFs(root.getPath());
		long blockSize = sf.getBlockSize();
		long blockCount = sf.getBlockCount();
		long availCount = sf.getAvailableBlocks();
		System.out.println("System Total Space:" + blockSize * blockCount / 1024/1024 + "M");
		System.out.println("System Remain Space:" + availCount * blockSize / 1024/1024 + "M");
	}