This question already has answers here:
What is a NullReferenceException, and how do I fix it?
(27 answers)
Closed 3 years ago.
Ive build an UI for a Touchdisplay on Rpi with Windows 10 iot Core.
When I tested this on my PC it worked. If I now test the software on the Raspberry I get an exception on this line(s):
lblTime.Text = DateTime.Now.ToShortTimeString();
lblDay.Text = DateTime.Now.ToString("dddd");
Its an exception of type 'System.NullReferenceException' what means this DateTime.Now is null Right?
The time is set on the Windows Device Portal so idk why there ist no "Now"-Time
I would guess, that lblTime and/or lblDay is null.
You can simply debug this by using a null check (if(lblTime == null) {)
I have now found the Problem. It was just to early(some first lines in the Main Page method), some Code later it worked fine.
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This question already has answers here:
What is a NullReferenceException, and how do I fix it?
(27 answers)
Closed 3 months ago.
This post was edited and submitted for review 3 months ago and failed to reopen the post:
Original close reason(s) were not resolved
I'm trying to do a little bit of cleaning up and I seem to be getting the follow
NullReferenceException: Object reference not set to an instance of an
object DestroyCollision.OnCollisionEnter2D (UnityEngine.Collision2D
collision) (at Assets/Scripts/DestroyCollision.cs:66)
Now though, even though the entire script works perfectly (there's literally no bugs or anything) and the object reference is set correctly (since the object in question gets its active state set to false), I am stumped as to why there are any issues. The following code is the line in question:
if (collision.gameObject.tag == "Shield")
{
GameObject.FindGameObjectWithTag("Shield").SetActive(false);
Destroy(this.gameObject);
}
The shield object is properly tagged, and as I said, setactive(false) gets applied. Line 66 is the gameobject.find... of that line of code there.
Why am I getting the error and how to fix it?
Are you sure you mean to have Destroy(this.gameObject); instead of Destroy(collision.gameObject);?
We know collision.gameObject is not null there, but you provide no info on what this.gameObject is.
This question already has answers here:
What is a NullReferenceException, and how do I fix it?
(27 answers)
Closed 11 months ago.
This is an old project of mine. i haven't opened it for some time. As far as i remember it was working perfectly fine. but today when i opend it it stopped working. i haven't change a single line of code. it just stopped working(it builds just fine but dont start after). After a full night of frustration i found the reason of why its not starting but couldn't imagine or find any possible solution, cause it was eorking perfectly fine but suddenly it decided to stop working.
Please help :)
i swear i haven't changed a single line of code. not even a coma.
It's because you have called PopulateGridViewEmployee with an empty searchKey which is an Optional Argument set to Null.
Hence you're getting System.ArgumentNullException
To fix it change the optional argument to have an empty string:
PopulateGridViewEmployee(string searchKey = "")
This question already has answers here:
C# set environment variable
(2 answers)
Ways to deploying console applications in C#
(5 answers)
Closed 4 years ago.
How can I make my console app installable so that when I open CMD I can run it from anywhere with a keyword. Like when I type in git in cmd for example. Thanks.
For this, you need to set up an environment variable called PATH. In Windows, it is in the registry. But for Mac or Linux you may want to update the .bash_profile file.
You can use the following function
SetEnvironmentVariable(String, String)
Here is the link for the MSDN .net core API
Then again I haven't tried this before. But hope this helps you out.
This question already has answers here:
Is there a "first run" flag in WP7
(3 answers)
Closed 9 years ago.
Is there any way to find out if the application has run for the first time; and if so, how do I access it?
There isn't a built in feature for this (that I know of), but you could use this bit of code. Is there a "first run" flag in WP7
Essentially you just want to use IsolatedStorage and write something there such as a boolean and check that each time the app is ran.
I had to do this on iPhone and Android to display a "Please rate us.." dialog on the first run. A simple solution for both cases, and Windows Phone as well, is to write out a file on the first run. Check for it when the app starts, if it's not there, you know it's the first run.
This question already has answers here:
Closed 12 years ago.
Possible Duplicate:
How to detect Windows 64 bit platform with .net?
How do you know if the operating system is x64 or x86 from a c# .net 2.0 windows applicaiton?
Also the applicaiton is 32bit.
Thanks
Use GetEnvironmentVariable to look for the PROCESSOR_ARCHITEW6432 variable. If it doesn't exist, you must be running 32bit:
bool is64bit = !string.IsNullOrEmpty(
Environment.GetEnvironmentVariable("PROCESSOR_ARCHITEW6432"));
EDIT:
Thanks to Hans Passant for pointing out the error in using the PROCESSOR_ARCHITECTURE variable.