[adn258]

Ok I'm assuming that it converts different types but why wouldn't you use parse? Or am I even right about that.

For example in the below code

pictureBox1.Top= (int)(pictureBox1.Top - (pictureBox1.Height * 0.025)); 
pictureBox1.Left = (int)(pictureBox1.Left - (pictureBox1.Width * 0.025));
pictureBox1.Height = (int)(pictureBox1.Height + (pictureBox1.Height* 0.05));
pictureBox1.Width = (int)(pictureBox1.Width + (pictureBox1.Width * 0.05));

Will zoom in on an image in a picturebox1 but why can't you use just

pictureBox1.Height = (PictureBox1.Height *2);

etc. etc.


I know this seems like a dumb question but yeah. What does (int) do to magically make this work.

[tlhIn`toq]

It's called casting.
It casts the result from whatever form it comes in to the specified form.

So it might cast a float to an int, for example.

---

Resources, references and suggestions for new programmers. - Updated Sep 2011

---

Spoiler

Finding answers to specific problems:
Sometimes just knowing where to look can make all the difference. Google is your friend.
Search with either "C#" or "MSDN" as the first word: "MSDN Picturebox", "C# Custom Events", "MSDN timer" etc.
How to do a good search that will get you targeted answers.

Once you have that MSDN page that describes the function, you may not be familiar with out to actually get useful information from that page. There is a LOT of data there. So what is the important parts? Read this guide to reading the MSDN.

Don't think you are the first person to ask a question. Try a search on this site to see if someone has already brought up this problem. Also, as soon as you post your question go to the bottom of the updated page: You will see where the system has already analyzed your question and tried to find similar threads for the same question, so check those links out.

But honestly, just typing away and seeing what pops up in Intellisense is going to make your self-education take 20 years. You can learn by trying to reverse engineer the language through banging on the keyboard experimentation - or you can learn by doing the tutorials and following a good "How to learn C#" book. There are so many great "How do I build my first application" tutorials on the web... There are dozens of "Learn C# in 21 days", "My first C# program" type books at your local book seller or even public library.

Beginner:
Build a Program Now! in Visual C# by Microsoft Press, ISBN 0-7356-2542-5 is a terrific book that has you build a Windows Forms application, a WPF app, a database application, your own web browser.

Visual Studio Keyboard Shortcuts

D.I.C. C# Resource page Start here
Intro to C# online tutorial then here...
C# control structures then here.
MSDN Beginner Developer video series
MSDN video on OOP principals, making classes, constructors, accessors and method overloading
MSDN Top guideline violations, know what to avoid before you do it.
Design patterns as diagrams

I hate sending people to another site when we have such good tutorials here, but this series shouldn't be overlooked.
Programming OOP in C# - Part 1
Programming OOP in C# - Part 2
Programming OOP in C# - Part 3
Programming OOP in C# - Part 4
Programming OOP in C# - Part 5

Writing a text file is always one of the first things people want to do, in order to store data like high-scores, preferences and so on.
Writing a text file tutorial.
Reading a text file tutorial.

Have you seen the 500+ MSDN Code Samples? They spent a lot of time creating samples and demos. It seems a shame to not use them.

Intermediate:
The tutorials below walk through making an application including inheritance, custom events and custom controls, object serialization and more.
Bulding an application - Part 1
Building an application - Part 2
Quick and easy custom events
Separating data from GUI - PLUS - serializing the data to XML
Passing values between forms/classes
Decouple your multi-threaded work from the GUI so forms don't hang

Working with environmental variables
'Why do we use delegates?' thread
And everyone always wants to connect to a database, right out of the gate so Database tutorials right here on DIC

C# Cookbooks
Are a great place to get good code, broken down by need, written by coding professionals. You can use the code as-is, but take the time to actually study it. These professionals write in a certain style for a reason developed by years of experience and heartache.

Everyone:
Debugging tutorial
Debugging tips
Debugging in detail
Great debugging tips
It still doesn't work, article

I urge you to work through the C# learning series here on DIC, and to work a self-teaching book from cover to cover before you even think about designing your own applications.
Microsoft Visual Studio Tips, 251 ways to improve your productivity, Microsoft press, ISBN 0-7356-2640-5 Has many, many great, real-world tips that I use all the time.

These are just good every-day references to put in your bookmarks.
MSDN C# Developers Center with tutorials
Welcome to Visual Studio
Free editions of Visual Studio 2010

Let me also throw in a couple tips:

• You have to program as if everything breaks, nothing works, the cyberworld is not perfect, the attached hardware is flakey, the network is slow and unreliable, the harddrive is about to fail, every method will return an error and every user will do their best to break your software. Confirm everything. Range check every value. Make no assumptions or presumptions.
  
  
• Take the extra 3 seconds to rename your controls each time you drag them onto a form. The default names of button1, button2... button54 aren't very helpful. If you rename them right away to something like btnOk, btnCancel, btnSend etc. it helps tremendously when you make the methods for them because they are named after the button by the designer.btnSend_Click(object sender, eventargs e) is a lot easier to maintain than button1_click(object sender, eventargs e)
  
  
• You aren't paying for variable names by the byte. So instead of variables names of a, b, c go ahead and use meaningful names like Index, TimeOut, Row, Column and so on. You should avoid 'T' for the timer. Amongst other things 'T' is commonly used throughout C# for Type and this will lead to problems. There are naming guidelines you should follow so your code confirms to industry standards. It makes life much easier on everyone around you, including those of us here to help. If you start using the standards from the beginning you don't have to retrain yourself later.
  
  
• Try to avoid having work actually take place in GUI control event handlers. It is usually better to have the GUI handler call other methods so those methods can be reused and make the code more readible.
  
  Spoiler

  
  

  btnSave(object sender, eventargs e)
  {
      SavePreferences();
  }
  
  SaveMenuItem(object sender, eventargs e)
  {
      SavePreferences();
  }
  
  SaveContextMenu(object sender, eventargs e)
  {
      SavePreferences();
  }
  
  FormMain_Closing(object sender, eventargs e)
  {
      if (IsDirty) SavePreferences();
  }
  

  
  
  
• I strongly suggest installing VMware or some other virtualization technology on your development PC so you can create a couple virtual computers for testing. This would allow you to debug and test inside: WinXP32, XP64, Vista, Win7x32, Win7x64... etc. without having to actually have 5 physical PC's. Visual Studio will let you send the debug directly into one of these virtual machines so you can watch it operate, check its variables, see the crashes and so on just as if it were debugging on your real machine.
  
  
• This can't be stressed enough in today's world of cell phone messaging:
  Don't use txt/sms/leet/T9 speak like: u no, u r, dnt, wut i m do-n, coz, al gud, b4, ny1, and so on like this guy:
  
  dis not b d'hood dawg... You are sitting at a real keyboard with a real monitor, not a cell phone. You are not here texting your high school posse to come to your kegger after their shift at Taco Bell. You are here asking for help from senior coding professionals who graciously donate their valuable time to helping the next generation of coders with their chosen craft. Please try to show them, yourself and the industry some respect by writing at least at an eighth grade level. (IE: English not ebonics or SMS, real words, punctuation and so on). If you can't take your own problem/question seriously enough to write like an adult, then why would you expect anyone else to take it seriously?

[modi123_1]

It's a short cut way of expressly converting your types. It shows you what you want to convert it to versus letting the compiler decide or typing something long out.

It operates like the 'Convert.to<x>' class.
http://msdn.microsof...y/bds4fye2.aspx

[adn258]

tlhIn`toq, on 18 September 2011 - 12:59 PM, said:

It's called casting.
It casts the result from whatever form it comes in to the specified form.

So it might cast a float to an int, for example.

---

Resources, references and suggestions for new programmers. - Updated Sep 2011

---

Spoiler

Finding answers to specific problems:
Sometimes just knowing where to look can make all the difference. Google is your friend.
Search with either "C#" or "MSDN" as the first word: "MSDN Picturebox", "C# Custom Events", "MSDN timer" etc.
How to do a good search that will get you targeted answers.

Once you have that MSDN page that describes the function, you may not be familiar with out to actually get useful information from that page. There is a LOT of data there. So what is the important parts? Read this guide to reading the MSDN.

Don't think you are the first person to ask a question. Try a search on this site to see if someone has already brought up this problem. Also, as soon as you post your question go to the bottom of the updated page: You will see where the system has already analyzed your question and tried to find similar threads for the same question, so check those links out.

But honestly, just typing away and seeing what pops up in Intellisense is going to make your self-education take 20 years. You can learn by trying to reverse engineer the language through banging on the keyboard experimentation - or you can learn by doing the tutorials and following a good "How to learn C#" book. There are so many great "How do I build my first application" tutorials on the web... There are dozens of "Learn C# in 21 days", "My first C# program" type books at your local book seller or even public library.

Beginner:
Build a Program Now! in Visual C# by Microsoft Press, ISBN 0-7356-2542-5 is a terrific book that has you build a Windows Forms application, a WPF app, a database application, your own web browser.

Visual Studio Keyboard Shortcuts

D.I.C. C# Resource page Start here
Intro to C# online tutorial then here...
C# control structures then here.
MSDN Beginner Developer video series
MSDN video on OOP principals, making classes, constructors, accessors and method overloading
MSDN Top guideline violations, know what to avoid before you do it.
Design patterns as diagrams

I hate sending people to another site when we have such good tutorials here, but this series shouldn't be overlooked.
Programming OOP in C# - Part 1
Programming OOP in C# - Part 2
Programming OOP in C# - Part 3
Programming OOP in C# - Part 4
Programming OOP in C# - Part 5

Writing a text file is always one of the first things people want to do, in order to store data like high-scores, preferences and so on.
Writing a text file tutorial.
Reading a text file tutorial.

Have you seen the 500+ MSDN Code Samples? They spent a lot of time creating samples and demos. It seems a shame to not use them.

Intermediate:
The tutorials below walk through making an application including inheritance, custom events and custom controls, object serialization and more.
Bulding an application - Part 1
Building an application - Part 2
Quick and easy custom events
Separating data from GUI - PLUS - serializing the data to XML
Passing values between forms/classes
Decouple your multi-threaded work from the GUI so forms don't hang

Working with environmental variables
'Why do we use delegates?' thread
And everyone always wants to connect to a database, right out of the gate so Database tutorials right here on DIC

C# Cookbooks
Are a great place to get good code, broken down by need, written by coding professionals. You can use the code as-is, but take the time to actually study it. These professionals write in a certain style for a reason developed by years of experience and heartache.

Everyone:
Debugging tutorial
Debugging tips
Debugging in detail
Great debugging tips
It still doesn't work, article

I urge you to work through the C# learning series here on DIC, and to work a self-teaching book from cover to cover before you even think about designing your own applications.
Microsoft Visual Studio Tips, 251 ways to improve your productivity, Microsoft press, ISBN 0-7356-2640-5 Has many, many great, real-world tips that I use all the time.

These are just good every-day references to put in your bookmarks.
MSDN C# Developers Center with tutorials
Welcome to Visual Studio
Free editions of Visual Studio 2010

Let me also throw in a couple tips:

• You have to program as if everything breaks, nothing works, the cyberworld is not perfect, the attached hardware is flakey, the network is slow and unreliable, the harddrive is about to fail, every method will return an error and every user will do their best to break your software. Confirm everything. Range check every value. Make no assumptions or presumptions.
  
  
• Take the extra 3 seconds to rename your controls each time you drag them onto a form. The default names of button1, button2... button54 aren't very helpful. If you rename them right away to something like btnOk, btnCancel, btnSend etc. it helps tremendously when you make the methods for them because they are named after the button by the designer.btnSend_Click(object sender, eventargs e) is a lot easier to maintain than button1_click(object sender, eventargs e)
  
  
• You aren't paying for variable names by the byte. So instead of variables names of a, b, c go ahead and use meaningful names like Index, TimeOut, Row, Column and so on. You should avoid 'T' for the timer. Amongst other things 'T' is commonly used throughout C# for Type and this will lead to problems. There are naming guidelines you should follow so your code confirms to industry standards. It makes life much easier on everyone around you, including those of us here to help. If you start using the standards from the beginning you don't have to retrain yourself later.
  
  
• Try to avoid having work actually take place in GUI control event handlers. It is usually better to have the GUI handler call other methods so those methods can be reused and make the code more readible.
  
  Spoiler

  
  

  btnSave(object sender, eventargs e)
  {
      SavePreferences();
  }
  
  SaveMenuItem(object sender, eventargs e)
  {
      SavePreferences();
  }
  
  SaveContextMenu(object sender, eventargs e)
  {
      SavePreferences();
  }
  
  FormMain_Closing(object sender, eventargs e)
  {
      if (IsDirty) SavePreferences();
  }
  

  
  
  
• I strongly suggest installing VMware or some other virtualization technology on your development PC so you can create a couple virtual computers for testing. This would allow you to debug and test inside: WinXP32, XP64, Vista, Win7x32, Win7x64... etc. without having to actually have 5 physical PC's. Visual Studio will let you send the debug directly into one of these virtual machines so you can watch it operate, check its variables, see the crashes and so on just as if it were debugging on your real machine.
  
  
• This can't be stressed enough in today's world of cell phone messaging:
  Don't use txt/sms/leet/T9 speak like: u no, u r, dnt, wut i m do-n, coz, al gud, b4, ny1, and so on like this guy:
  
  dis not b d'hood dawg... You are sitting at a real keyboard with a real monitor, not a cell phone. You are not here texting your high school posse to come to your kegger after their shift at Taco Bell. You are here asking for help from senior coding professionals who graciously donate their valuable time to helping the next generation of coders with their chosen craft. Please try to show them, yourself and the industry some respect by writing at least at an eighth grade level. (IE: English not ebonics or SMS, real words, punctuation and so on). If you can't take your own problem/question seriously enough to write like an adult, then why would you expect anyone else to take it seriously?

Thanks guys by the way.

[Curtis Rutland]

modi123_1, on 18 September 2011 - 02:59 PM, said:

It's a short cut way of expressly converting your types. It shows you what you want to convert it to versus letting the compiler decide or typing something long out.

It operates like the 'Convert.to<x>' class.
http://msdn.microsof...y/bds4fye2.aspx

Well, this might be more technical than the OP wanted, but casting is not the same as converting. You can't cast a string to an int, but you can Convert.ToInt32 it. Just a point of clarification.

[tlhIn`toq]

Agreed. Which is why I phrased it as 'casting'. Because putting a type in parenthesis is not converting, and does not act like convert.to.... as earlier mentioned. I just wasn't going to make a deal out of it. But since it has been brought up.



As you can see, using Curtis' example, if you try to cast an int to a string in the way you questioned it will fail and you will be told you cannot cast in that direction.

But on the next line we perform an explicit Convert.To and that is legal.

So, Modi, hate to say it but (int)somevalue is not like Convert. It is casting.

[Momerath]

tlhIn`toq, on 19 September 2011 - 08:44 AM, said:

But on the next line we perform an explicit Convert.To and that is legal.

Just to throw some more terms into the fray:

There are two types of casting: implicit and explicit.

Implicit casting is done without you having to specify the type to cast into, the compiler does this for you. An example is

int a = 5;
double d = a;

Here we see the Int32 type being cast into the Double type, but we don't tell it that is what we want.

Explicit casting requires that you specify the type to cast into. An example of this is

double d = 5.0;
int a = (int)d;

Without the type specifier, the compiler will complain and tell you that it can't do this implicitly and that an explicit cast exists.

For your own types you can create casts, both implicit and explicit

class Example {
    public int Value { get; private set; }
    public Example(int v) {
        Value = v;
    }

    static public implicit operator Example(int i) {
        return new Example(i);
    }

    static public explicit operator Int32(Example e) {
        return Value;
    }
}

With that class, we can now do this

int i = 15;
Example e = i;  // implicit

i = (Int32)e;  // explicit