How to open current working directory if a certain folder doesn't exists in the directory?

So here is my code on a pushbutton callback:

prompt = {'Enter Patient Name or ID:'};

title = 'Input';

num_lines = 1;

defaultans = {'Patient'};

answer = inputdlg(prompt,title,num_lines,defaultans);

handles.file = cellstr(answer{1});

%Creating a new folder by the name of Patient's name that user entered

folder = handles.file{1}

guidata(hObject, handles);

mkdir(folder);

By far its working fine, now in a different pushbutton callback I want to display an error if the folder of same name already exists

folder = handles.file{1}

if exist(folder,'dir')

      winopen(folder);

else

      winopen(pwd);

end

But it shows error : Reference to non-existent field 'file'. Please Help. Thanks in advance

[Guillaume]

Why would you think that isfield or iscellstr would tell you whether a folder already exist? Where in their documentation is there even a hint that these functions have anything to do with folders?

[Adam]

Original question related to how to test if a directory exists or not.

[Rena Berman]

(Answers Dev) Restored Question.

[Stephen23]

http://web.archive.org/web/20210214185451/https://www.mathworks.com/matlabcentral/answers/320271-how-to-open-current-working-directory-if-a-certain-folder-doesn-t-exists-in-the-directory

Answer 1

[Adam]

if exist( folder, 'dir' )

will test if a folder exists or not on the file system. Judging by your attempts at it though I'm not sure that is what you are asking for since you are checking if it exists on handles or if it is a string cell.

[Adam]

Well, you seem to have the warning part fine, so the above will give you the rest.

[Adam]

What is 'folder'?

The field 'file' is not even being referred to in that statement.

[Adam]

Well, that is a totally different error then. How did you get to the point in your code above to say that iscellstr doesn't work if the line above it throws an error anyway? My code should not have any impact on that.

Assuming this code is not in the same function as when you added the field to handles you appear to be missing a

guidata( hObject, handles )

(well, you are definitly missing it since you add something to handles which will then no longer be there when your function comes to an end because 'handles' in your pushbutton callback is a copy of the handles in the GUI at the start of your function. Without the above line that copy will not get written back to the GUI and will just go out of scope when the callback ends).

[Adam]

The guidata needs to be after the code in which you assign 'file' to 'handles', not when you access it.

I don't understand how you can be getting the error only sometimes. Either 'file' is a field or it isn't unless you keep clearing it or doing different things each time you run it.

winopen( pwd )

should not care whether 'file' exists on handles or not.

[Adam]

Then you must be doing something else in code you haven't shared as this error does not make sense.