Get user field category

Question

I have a matrix that contains a block with a category field. I want to loop over the matrix models, in PHP, to get data. Here's what I have so far:

foreach ($user->networksMatrix as $key => $networkLink)
{
    $netArr[$networkLink->id]["fields"]["networktype"] = $networkLink->networktype;
    $netArr[$networkLink->id]["fields"]["networkUrl"] = $networkLink->networkUrl;
}

networktype is a category field. How do I get the get the ID of the category a user selected?

Thanks!

UPDATE

I discovered that the following works:

foreach ($user->networksMatrix as $key => $networkLink)
{
    $netArr[$networkLink->id]["fields"]["networktype"] = $networkLink->networktype->ids()[0];
    $netArr[$networkLink->id]["fields"]["networkUrl"] = $networkLink->networkUrl;
}

Since networktype is a categories field and that field is limited to 1 category I'll only ever get a single result from the method:

ids();

So... I just do this and I'm good:

$networkLink->networktype->ids()[0];

Answer 1

For the sake of completeness, the question was resolved by the asker and I will quote his answer here, so this fine question is recognized by Stack Exchange as answered!

Matt V says:

I discovered that the following works:

foreach ($user->networksMatrix as $key => $networkLink)
{
    $netArr[$networkLink->id]["fields"]["networktype"] = $networkLink->networktype->ids()[0];
    $netArr[$networkLink->id]["fields"]["networkUrl"] = $networkLink->networkUrl;
}

Since networktype is a categories field and that field is limited to 1 category I'll only ever get a single result from the method:

ids();

So... I just do this and I'm good:

$networkLink->networktype->ids()[0];