（转自：http://www.cnblogs.com/qsl568/archive/2012/03/14/2395636.html）
获取当前应用的版本号：
private String getVersionName() throws Exception
{
// 获取packagemanager的实例
PackageManager packageManager = getPackageManager();
// getPackageName()是你当前类的包名，0代表是获取版本信息
PackageInfo packInfo = packageManager.getPackageInfo(getPackageName(),0);
String versionName = packInfo.versionName;
String versionCode = packInfo.versionCode;
return version;
}
获取当前系统的版本号：
textView.setText("Product Model: " + android.os.Build.MODEL + ","
+ android.os.Build.VERSION.SDK + ","
+ android.os.Build.VERSION.RELEASE);
或：
/*
*
* Build.VERSION_CODES
1 (0x00000001) Android 1.0 BASE
2 (0x00000002) Android 1.1 BASE_1_1
3 (0x00000003) Android 1.5 CUPCAKE
4 (0x00000004) Android 1.6 DONUT
5 (0x00000005) Android 2.0 ECLAIR
6 (0x00000006) Android 2.0.1 ECLAIR_0_1
7 (0x00000007) Android 2.1 ECLAIR_MR1
8 (0x00000008) Android 2.2 FROYO
9 (0x00000009) Android 2.3 GINGERBREAD
10 (0x0000000a) Android 2.3.3 GINGERBREAD_MR1
11 (0x0000000b) Android 3.0 HONEYCOMB
12 (0x0000000c) Android 3.1 HONEYCOMB_MR1
13 (0x0000000d) Android 3.2 HONEYCOMB_MR2*/
/*获取当前系统的android版本号*/
int currentapiVersion=android.os.Build.VERSION.SDK_INT;