Save multiple image profiles to SQL Server database from Xamarin.Forms - xamarin.forms

Question

I am creating a cross platform school app. I have a page that displays the students in a class and their pictures. I added a functionality that enables the teacher to change the profile of the student or add one if none. the thing is that this functionality works great on android in which they can change or add multiple profiles for different students at once. but on ios, something seems wrong. If they add multiple pics, the pictures won't be uploaded to my database and thus no pics are displayed, but if they add only one pic for a student, it will be uploaded.
Here is my code:
private void generateProfiles(double width, List<studentdetailsformanagment> lstofstudents,List<absenteesIds>attending)
{
studentprofiles.Children.Clear();
dtAttedndance.Clear();
double nbofcolumns = width / 180;
double nbofrows = lstofstudents.Count / nbofcolumns;
for (int i = 0; i < nbofcolumns-1; i++)
{
studentprofiles.ColumnDefinitions.Add(new ColumnDefinition { Width = 170 });
}
for (int j = 0; j < nbofrows + 1; j++)
{
studentprofiles.RowDefinitions.Add(new RowDefinition { Height = 170 });
}
for (int i = 0; i < lstofstudents.Count; i++)
{
var student = lstofstudents[i];
DataRow dtdr = dt.Select("[id] ='" + student.id + "'").FirstOrDefault();
if (dtdr == null)
dt.Rows.Add(Preferences.Get("AcademicYearId", ""),student.id, section.Text, student.profilePic);
SwipeItem delete = new SwipeItem
{
Text = "Remove",
BackgroundColor = Color.Transparent
};
SwipeItems items = new SwipeItems
{
Mode = SwipeMode.Execute
};
items.Add(delete);
List<SwipeItem> swipeItems = new List<SwipeItem>() { delete };
Image img = new Image
{
Source = ImageSource.FromResource("ALNahrainAlphaApp.icons.user_profile.png"),
Aspect = Aspect.AspectFill,
Margin = -20,
HeightRequest = 100,
WidthRequest = 100,
};
if (student.profilePic == null)
img.Source = ImageSource.FromResource("ALNahrainAlphaApp.icons.user_profile.png");
else
{
byte[] bytes = System.Convert.FromBase64String(student.profilePic);
img.Source = ImageSource.FromStream(() => new MemoryStream(bytes));
}
StackLayout stdinfo = new StackLayout { Orientation = StackOrientation.Vertical, ClassId="false" };
if (attending.Count > 0)
{
for (int j = 0; j < attending.Count; j++)
{
if (student.id == attending[j].id)
{
stdinfo.BackgroundColor = Color.FromHex("#0d98ba");
stdinfo.ClassId = "true";
}
}
}
Label stdname = new Label { TextColor = Color.Black, Text = student.name, VerticalOptions = LayoutOptions.Center, HorizontalOptions = LayoutOptions.Center };
Frame circleImageFrame = new Frame
{
ClassId = student.id,
Margin = 10,
BorderColor = Color.Black,
CornerRadius = 50,
HeightRequest = 60,
WidthRequest = 60,
IsClippedToBounds = true,
HorizontalOptions = LayoutOptions.Center,
VerticalOptions = LayoutOptions.Center,
Content = img
};
stdinfo.Children.Add(circleImageFrame);
stdinfo.Children.Add(stdname);
SwipeView swipe = new SwipeView
{
Threshold=70,
LeftItems = new SwipeItems(items),
Content = stdinfo,
};
AddTap.Tapped += async (s, evt) =>
{
try
{
await PickAndShow(null, img);
byte[] profilepic = System.IO.File.ReadAllBytes(imgpath);
string imageBase64 = Convert.ToBase64String(profilepic);
try
{
DataRow dr = dt.Select("[id] ='" + circleImageFrame.ClassId + "'").FirstOrDefault();
if (dr != null) dr["profilePic"] = imageBase64;
var obj = stdprofiles.FirstOrDefault(x => x.id == circleImageFrame.ClassId);
if (obj != null) obj.profilePic = imageBase64;
}
catch (Exception exp)
{
await DisplayAlert("Error", exp.Message, "ok");
}
}
catch(Exception exp)
{
}
};
circleImageFrame.GestureRecognizers.Add(AddTap);
this is the function i use to display circular frames with profiles.
async Task<FileResult> PickAndShow(PickOptions options, Image image)
{
imgpath = "";
try
{
var result = await FilePicker.PickAsync(options);
if (result != null)
{
Text = $"File Name: {result.FileName}";
if (result.FileName.EndsWith("jpg", StringComparison.OrdinalIgnoreCase) ||
result.FileName.EndsWith("png", StringComparison.OrdinalIgnoreCase))
{
stream = await result.OpenReadAsync();
image.Source = ImageSource.FromStream(() => stream);
}
}
imgpath = result.FullPath;
return result;
}
catch (Exception ex)
{
}
return null;
}
and this is the function i use to pick an image from the folders in the device
this is the code that runs when i press submit:
async private void submit_Clicked(object sender, EventArgs e)
{
submit.IsEnabled = false;
if (flagEditorAttednd == true)
{
flagEditorAttednd = false;
edit.Source = ImageSource.FromResource("ALNahrainAlphaApp.icons.edit.png");
select.IsEnabled = false;
urlClass urldata = new urlClass();
string uri = urldata.url + "/PostStdDetails";
StringContent content = new StringContent(JsonConvert.SerializeObject(dt), Encoding.UTF8, "application/json");
try
{
HttpResponseMessage responsepost = await client.PostAsync(uri, content);
if (responsepost.IsSuccessStatusCode == true)
{
string outcome = await responsepost.Content.ReadAsStringAsync();
var result = JsonConvert.DeserializeObject<string>(outcome);
await DisplayAlert("Students Distribution", "Students in section " + section.Text + " were edited successfully", "OK");
var width = this.Width;
generateProfiles(width, stdprofiles, absentstds);
nbofstds.Text = stdprofiles.Count.ToString() + " Students";
submit.IsEnabled = true;
}
else
{
await DisplayAlert("Operation Failed", "Response Failed!", "Cancel");
submit.IsEnabled = true;
}
}
catch (System.Net.WebException exp)
{
submit.IsEnabled = true;
bool ans = await DisplayAlert("Connection Failed", "Please Check Your Internet Connection!", "Retry", "Cancel");
if (ans == true)
submit_Clicked(sender, e);
}
catch (Exception exp)
{
submit.IsEnabled = true;
bool ans = await DisplayAlert("Connection Failed", exp.Message, "Retry", "Cancel");
if (ans == true)
submit_Clicked(sender, e);
}
}
this is the code at the sql server side:
ALTER PROCEDURE [dbo].[getstddetailsupdate]
#stdDetailsTable as StdDetailsTypeTable readonly
AS
Begin
update [dbo].[students]
set [section]= X.section, [profilePic]=X.profilePic
FROM [dbo].[students],#stdDetailsTable X where [dbo].[students].id=X.id and [dbo].[students].YearId=X.YearId
end
this is how they appear:
when they tap on the circular frame, they can choose a pic and when they click submit, the pics chosen for each student will be uploaded. the problem is that when many pics are chosen, no pictures are uploaded. but if only one is chosen, it will be uploaded normally. why is that? i can't figure out why this is happening. thanks in advance