invalidargumentexception

I have some code like this $editStuState = StuAtt::where('studentId' , '=' , $id)->first(); $editStuState -> leave +=1; $editStuState -> present = $editStuState -> present-1; $editStuState->update(); //OR $editStuState->save(); return 'this is good'; I can't save or Update my data, when I remove Update and Save related line it can print text. this is the dd($editStuState) data StuAtt {#382 ▼ #table: "stu_attendance" #connection: "mysql" #primaryKey: "id" #keyType: "int" +incrementing: true #with: [] #withCount: [] #perPage: 15 +exists: true +wasRecentlyCreated: false #attributes: array:7 [▼

This question already has an answer here: C# network connection running from shared drive 1 answer I asked a similar question to this a few days ago. At that point, I was trying to use sockets. Currently, I am using TCPClient to do the dirty socket work for me. I am using Windows 7 and Visual studios 2013 Professional. Original and Current Project Outline: I need to create an application (WinForms using C#) that allows the user to connect to a device (a piece of hardware that will be sent arguments/commands) via wifi (wifi is end goal but I am settling at the moment for any connection) and

I got an error like this - * Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: **-[NSCFDictionary initWithObjects:forKeys:count:]: attempt to insert nil value at objects[0] (key: searched)' Then I tried the below code if (Obj == (id)[NSNull null]) //Obj is an id { NSLog(@" Obj is (id)[NSNull null]"); } else if (Obj == nil) { NSLog(@"Obj is nil"); } else if (Obj == NULL) { NSLog(@"Obj is NULL"); } else { NSLog(@"Obj is something else"); } searchedDict = [NSDictionary dictionaryWithObject:Obj forKey:@"searched"]; And I got the NSLog message as 'Obj is nil'. But when