Android 获取包名，版本信息及VersionName名称

<span style="font-size: 14px;">private String getAppInfo() {
        try {
            String pkName = this.getPackageName();
            String versionName = this.getPackageManager().getPackageInfo(
                    pkName, 0).versionName;
            int versionCode = this.getPackageManager()
                    .getPackageInfo(pkName, 0).versionCode;
            return pkName + "   " + versionName + "  " + versionCode;
        } catch (Exception e) {
        }
        return null;
    }</span>