Android 4.4以下 选择图片是可以获取到图片路径的.高于Android 4.4获取图片路径只是获取到一个图片编号. 所以需要针对Android版本进行路径解析：
#region 高于 v4.4 版本 解析真实路径
public static String GetPath(Context context,Android.Net.Uri uri)
{ bool isKitKat = Build.VERSION.SdkInt >= BuildVersionCodes.Kitkat; // DocumentProvider
if (isKitKat && DocumentsContract.IsDocumentUri(context, uri))
{
// ExternalStorageProvider
if (isExternalStorageDocument(uri))
{
String docId = DocumentsContract.GetDocumentId(uri);
String[] split = docId.Split(':');
String type = split[]; if ("primary".Equals(type.ToLower()))
{
return Android.OS.Environment.ExternalStorageDirectory + "/" + split[];
} // TODO handle non-primary volumes
}
// DownloadsProvider
else if (isDownloadsDocument(uri))
{ String id = DocumentsContract.GetDocumentId(uri);
Android.Net.Uri contentUri = ContentUris.WithAppendedId(
Android.Net.Uri.Parse("content://downloads/public_downloads"),long.Parse(id)); return getDataColumn(context, contentUri, null, null);
}
// MediaProvider
else if (isMediaDocument(uri))
{
String docId = DocumentsContract.GetDocumentId(uri);
String[] split = docId.Split(':');
String type = split[]; Android.Net.Uri contentUri = null;
if ("image".Equals(type))
{
contentUri = MediaStore.Images.Media.ExternalContentUri;
}
else if ("video".Equals(type))
{
contentUri = MediaStore.Video.Media.ExternalContentUri;
}
else if ("audio".Equals(type))
{
contentUri = MediaStore.Audio.Media.ExternalContentUri;
} String selection = "_id=?";
String[] selectionArgs = new String[] {
split[]
}; return getDataColumn(context, contentUri, selection, selectionArgs);
}
}
// MediaStore (and general)
else if ("content".Equals(uri.Scheme.ToLower()))
{ // Return the remote address
if (isGooglePhotosUri(uri))
return uri.LastPathSegment; return getDataColumn(context, uri, null, null);
}
// File
else if ("file".Equals(uri.Scheme.ToLower()))
{
return uri.Path;
} return null;
} /**
* Get the value of the data column for this Uri. This is useful for
* MediaStore Uris, and other file-based ContentProviders.
*
* @param context The context.
* @param uri The Uri to query.
* @param selection (Optional) Filter used in the query.
* @param selectionArgs (Optional) Selection arguments used in the query.
* @return The value of the _data column, which is typically a file path.
*/
public static String getDataColumn(Context context,Android.Net.Uri uri, String selection,
String[] selectionArgs)
{ ICursor cursor = null;
String column = "_data";
String[] projection = {
column
}; try
{
cursor = context.ContentResolver.Query(uri, projection, selection, selectionArgs,
null);
if (cursor != null && cursor.MoveToFirst())
{
int index = cursor.GetColumnIndexOrThrow(column);
return cursor.GetString(index);
}
}
finally
{
if (cursor != null)
cursor.Close();
}
return null;
} /**
* @param uri The Uri to check.
* @return Whether the Uri authority is ExternalStorageProvider.
*/
public static bool isExternalStorageDocument(Android.Net.Uri uri)
{
return "com.android.externalstorage.documents".Equals(uri.Authority);
} /**
* @param uri The Uri to check.
* @return Whether the Uri authority is DownloadsProvider.
*/
public static bool isDownloadsDocument(Android.Net.Uri uri)
{
return "com.android.providers.downloads.documents".Equals(uri.Authority);
} /**
* @param uri The Uri to check.
* @return Whether the Uri authority is MediaProvider.
*/
public static bool isMediaDocument(Android.Net.Uri uri)
{
return "com.android.providers.media.documents".Equals(uri.Authority);
} /**
* @param uri The Uri to check.
* @return Whether the Uri authority is Google Photos.
*/
public static bool isGooglePhotosUri(Android.Net.Uri uri)
{
return "com.google.android.apps.photos.content".Equals(uri.Authority);
} #endregion