C#•8mo ago

Placeholder property seems to be missing from textbox?

Could someone please inform about any possible reasons as to why this property is missing?

99 Replies

Spore355OP•8mo ago

I am trying to make a search bar for my Winform app, and I want a placeholder for my search bar so that it is clear to the user what they are interacting with, but the property of the textbox seems to be missing.

Angius•8mo ago

It's called PlaceholderText IIRC

Spore355OP•8mo ago

I have sorted the properties alphabetically, and it is only displaying PasswordChar

Spore355OP•8mo ago

This is what I can see

Angius•8mo ago

I wonder if you need to set it with code, for some reason

Spore355OP•8mo ago

Have you ever had this issue before, or had to do something similar?

Angius•8mo ago

I never used Winforms Well, sorry, once in college I made a shitty calculator with it

Spore355OP•8mo ago

Ah, I see Do you know of any packages that I can install to add more items to my toolbox? Perhaps I can download a toolbox add on? Does that exist?

Angius•8mo ago

There are nugets with additional Winforms controls, yes $winforms

MODiX•8mo ago

https://images-ext-1.discordapp.net/external/TKI5abO7_JAhdMvgfJ7ckxftCkZik5I8D6xDZ0CZwrY/https/i.imgur.com/Z9HMTAg.png

Imgur

Angius•8mo ago

Uh, wrong tag Sec

Spore355OP•8mo ago

Bruh, I swear it's not even that advanced of a project Just a symbol/character library Still, definitely more complicated than anythin i've ever done before Also, what is MODiX?

Angius•8mo ago

It's the bot running on the server And, you are correct, it's not that advanced Not sure why you're asking for 3rd party controls There's no $winformsuilibs tag, alas

Spore355OP•8mo ago

I am struggling to make it work

Angius•8mo ago

Does the placeholder property not work from code?

Spore355OP•8mo ago

I don't know how to use that

Angius•8mo ago

Ah Well, might I suggest looking for some Winforms tutorial, then? You should have a .cs file with the code behind the form There, in the constructor probably, you might be able to set whatever properties of any control

Spore355OP•8mo ago

I have Form1.cs, and Form1.Designer.cs I have been using Form1.cs, but I still don't know how to reference a specific object Like a textbox For the datatables, I just instantiated them in the Form1.cs, and then stacked them on top of eachother to simulate drop down menus, before then linking those to datagridview tables, which are what display my characters Could you recommend something? I have looked at some before, but they never proved to be very useful to my project

Angius•8mo ago

https://learn.microsoft.com/en-us/visualstudio/ide/create-csharp-winform-visual-studio?view=vs-2022

Create a Windows Forms app with C# - Visual Studio (Windows)

Create a Windows Forms app in Visual Studio with C#, add button controls to the form, and run the code to test your application.

Angius•8mo ago

Microsoft documentation is always a good place to start

Spore355OP•8mo ago

In fact, I was following a winform tutorial before creating this thread asking about the placeholder property, which doesn't seem to exist on my property list Thank you I am still confused as to why that place holder is missing though

Angius•8mo ago

¯\_(ツ)_/¯ Could be you're using an older version of .NET that doesn't have it, could be it's not exposed to the designer, idk

Spore355OP•8mo ago

What do you mean by being exposed to the designer?

Angius•8mo ago

It's there in the code but not here

Spore355OP•8mo ago

In the designer code?

Angius•8mo ago

In the TextBox code The TextBox is a class, defined with code

Spore355OP•8mo ago

Here is some of what I have in my designer

Angius•8mo ago

That class might have a property PlaceholderText This is not the designer, this is the code behind Just so we're clear

Spore355OP•8mo ago

This is what I see

Angius•8mo ago

It seems this.searchBar is your search bar Try the .CodeBehind property on it

Spore355OP•8mo ago

Is the designer the page where I can drag and drop things onto the app?

Angius•8mo ago

This is the designer, yes

Spore355OP•8mo ago

Ah ok Ah, well that's the textbox that I dragged in and labelled searchBar But it currently does not do anything What does this do?

Angius•8mo ago

Uh It's... a property Let me guess, you don't know C#?

Spore355OP•8mo ago

As I said, I am a beginner Quite inexperienced

Angius•8mo ago

I'd certainly recommend starting with anything that's not a UI application

Spore355OP•8mo ago

Well, this work is due soon, and I can't really afford to restart Although I would agree with you, this probably was not the best thing for me to choose Although my options were limited

Angius•8mo ago

To answer your question, then, properties are public accessor to the inner state of a class instance

Spore355OP•8mo ago

I had to us a database for my project, but it was either this, or use a website and use SQLite

Angius•8mo ago

A website would've been easier tbh

Spore355OP•8mo ago

I think I understand, but would you mind elaborating off of this? Perhaps, although some of my friends have been having a rough time as well

MODiX•8mo ago

Angius

REPL Result: Success

public class MyCoolTextbox
{
    public string PlaceholderText { get; set; }

    public void Show()
    {
        Console.WriteLine($"Enter whatever: [{PlaceholderText}]");
    }   
}

var tb = new MyCoolTextbox();
tb.PlaceholderText = "unga bunga";
tb.Show();

public class MyCoolTextbox
{
    public string PlaceholderText { get; set; }

    public void Show()
    {
        Console.WriteLine($"Enter whatever: [{PlaceholderText}]");
    }   
}

var tb = new MyCoolTextbox();
tb.PlaceholderText = "unga bunga";
tb.Show();

Console Output

Enter whatever: [unga bunga]

Enter whatever: [unga bunga]

Compile: 493.486ms | Execution: 43.467ms | React with ❌ to remove this embed.

Spore355OP•8mo ago

OOP?

Angius•8mo ago

Yes C# is an object-oriented language

Spore355OP•8mo ago

Damn, I had a really good OOP program that I made a while ago But when I sent my laptop in for repair, I didn't save it on a USB, so lost it By accident of course And now I can't remember how that stuff works

Angius•8mo ago

Use Github in future Free backup and versioning with Git

Spore355OP•8mo ago

I always have syncing issues What is is called when your variable tb references mycooltextbox? I have used that to make datatables? Also, can you make a new object by using var?

Angius•8mo ago

tb holds a reference to that instance of MyCoolTextbox var is for type inference

Spore355OP•8mo ago

I thought var was for variable declaration

Angius•8mo ago

It's the "figure out what type this is" type

Person p = new Person();
var p = new Person();
Person p = new();

Person p = new Person();
var p = new Person();
Person p = new();

are all eqivalent declarations They all do the exact same thing

Spore355OP•8mo ago

I see What do you mean by saying it holds a reference? Do you mean that it carries the same attributes as the parent class? And that tb is the child subclass?

Angius•8mo ago

The instance is stored on the 1782th shelf tb holds shelf:1782 A reference to where the instance of that class is in memory Not the instance itself Nor a copy of that instance

Spore355OP•8mo ago

Could you please expand your explanation? And also, what is the relevance of shelf:1782?

Angius•8mo ago

A computer memory is a set of boxes Each box has a number

Spore355OP•8mo ago

Yes I know this

Angius•8mo ago

The instance of the class is placed in one of those boxes

Spore355OP•8mo ago

You are talking about address locations in memory

Angius•8mo ago

The variable stores the number of that box

Spore355OP•8mo ago

Got it Wait hold up I thought that the box stores the variable?

Angius•8mo ago

That's why we can do

MODiX•8mo ago

Angius

REPL Result: Success

class Foo
{ 
    public int Bar { get; set; }
}

var a = new Foo();
a.Bar = 69;
var b = a;
var c = b;
var d = c;
d.Bar = 420;

a.Bar

class Foo
{ 
    public int Bar { get; set; }
}

var a = new Foo();
a.Bar = 69;
var b = a;
var c = b;
var d = c;
d.Bar = 420;

a.Bar

Result: int

Compile: 321.592ms | Execution: 34.129ms | React with ❌ to remove this embed.

Angius•8mo ago

a, b, c, and d all store a reference to the same box

Spore355OP•8mo ago

I am confused with the output of this program If b references a, c references b, and d references c, then why are a and d different?

Angius•8mo ago

They do not reference each other They store the same reference The value of a is, say, box18 Then, we assign that value to variable b, now it also holds box18 And so on References themselves are not passed by reference, if that makes sense

Spore355OP•8mo ago

Indirect addressing?

Angius•8mo ago

The number of the box is not stored in a box Direct a, b, c, and d store the exact same reference to the exact same place in memory

Spore355OP•8mo ago

??? Ok, so why is a.Bar = 69, and d.bar = 420, but then a.Bar outputs 420?

Angius•8mo ago

Because d stores the same reference So we go to box 18 Take what's inside And change it's Bar

Spore355OP•8mo ago

Ok, so does .Bar change what is inside of the memory box?

Angius•8mo ago

Yes That's how all classes work

Spore355OP•8mo ago

Why did you call it Bar?

Angius•8mo ago

No reason Could be whatever

Spore355OP•8mo ago

Ok So you were running that function relative to the variable a?

MODiX•8mo ago

Angius

REPL Result: Success

class UngaBunga
{ 
    public int Xyzzyx { get; set; }
}

var a = new UngaBunga();
a.Xyzzyx = 69;
var b = a;
var c = b;
var d = c;
d.Xyzzyx = 420;

a.Xyzzyx

class UngaBunga
{ 
    public int Xyzzyx { get; set; }
}

var a = new UngaBunga();
a.Xyzzyx = 69;
var b = a;
var c = b;
var d = c;
d.Xyzzyx = 420;

a.Xyzzyx

Result: int

Compile: 331.821ms | Execution: 33.981ms | React with ❌ to remove this embed.

Spore355OP•8mo ago

Thus taking up space complexity of 2 for that function? Similar to how a merge sort works, except it just creates 2 copies?

Angius•8mo ago

There are no copies

Spore355OP•8mo ago

Ok I have another question

Angius•8mo ago

There's only one instance of Foo

Spore355OP•8mo ago

What is the difference between a class and a function Fundamentally I know that they are very different But what are their different use cases ? Being used on a.Xyzzyx and d.Xyzzyx?

Angius•8mo ago

Both a and d reference the same box, with the same instance

Spore355OP•8mo ago

Oh Oh Oh Damnit Yes I am being a fool And so do b and c? Also, what is the point of using the getter and setter? When there isn't a getter or setter written into the code?

Angius•8mo ago

The getter and setter still runs It's just syntactic sugar over getter and setter functions from lesser languages That a.Bar = 1 runs the setter And a.Bar runs the getter $getsetdevolve

MODiX•8mo ago

class Foo
{
    private int _bar;

    public int GetBar()
    {
        return _bar;
    }

    public void SetBar(int bar)
    {
        _bar = bar;
    }
}

class Foo
{
    private int _bar;

    public int GetBar()
    {
        return _bar;
    }

    public void SetBar(int bar)
    {
        _bar = bar;
    }
}

can be shortened to

class Foo
{
    private int _bar;

    public int GetBar() => _bar;

    public void SetBar(int bar) => _bar = bar;
}

class Foo
{
    private int _bar;

    public int GetBar() => _bar;

    public void SetBar(int bar) => _bar = bar;
}

can be shortened to

class Foo
{
    private int _bar;
    public int Bar {
        get { return _bar; }
        set { _bar = value; }
    }
}

class Foo
{
    private int _bar;
    public int Bar {
        get { return _bar; }
        set { _bar = value; }
    }
}

can be shortened to

class Foo
{
    private int _bar;
    public int Bar {
        get => _bar;
        set => _bar = value;
    }
}

class Foo
{
    private int _bar;
    public int Bar {
        get => _bar;
        set => _bar = value;
    }
}

can be shortened to

class Foo
{
    public int Bar { get; set; }
}

class Foo
{
    public int Bar { get; set; }
}

Angius•8mo ago

A function (or a method as we call them in C#) is something an object can do, a class describes what that object is

Spore355OP•8mo ago

I see That makes sense But what is the point of making bar go to _bar?

Angius•8mo ago

In this particular example? No point But you have some logic in the setter So until we get the field keyword, you will need a backing field That way the property doesn't have to reference itself

Spore355OP•8mo ago

What do you mean by the field keyword? And why would the property references itself?

Angius•8mo ago

Ah, sorry, I got this thread mixed up with another one Nevermind what I said lol But, yeah, in the case above there's no point having a backing field But if you want to have some logic, it's a must

Spore355OP•8mo ago

Ok, but why? Is it to do with private and public variable types?

Angius•8mo ago

private string _name;
public string Name {
    get => _name;
    set => _name = value.ToUpper().Trim();
}

private string _name;
public string Name {
    get => _name;
    set => _name = value.ToUpper().Trim();
}

This, you cannot do without a _name field

public string Name {
    get => Name;
    set => Name = value.ToUpper().Trim();
}

public string Name {
    get => Name;
    set => Name = value.ToUpper().Trim();
}

This would cause an endless loop

Spore355OP•8mo ago

Because you would change the original value, which is not what you want to do?

Angius•8mo ago

Getting from the property would call the getter, which would attempt to get from the property which would call the getter, and so on ad infinitum

Spore355OP•8mo ago

How come? Oh Ok That makes sense Hence why you need to make a new variable

Angius•8mo ago

Basically, a

public string GetName()
{
    return GetName();
}

public string GetName()
{
    return GetName();
}

Spore355OP•8mo ago

And assign it the same value

Angius•8mo ago

Infinite recursion

Spore355OP•8mo ago

Yes Thank you for the help you have given me

Angius•8mo ago

Anytime

Gaming

Programming

Placeholder property seems to be missing from textbox?