You are such a great teacher. Many blessings to you. Simplicity is born out of a deeper understanding. Your tutorials are brilliant, like a breath of fresh air.
Glad you're still with us. Sounds like a crazy experience, that tsunami... Hopefully one day I will learn French or find a translated copy of your book. Interesting to see you coding!
You're my fav C# instructor. Period! I don't know what moment or who sparked the idea in your head that you decided to share your knowledge with the world, I'm just grateful that you did :-)
Tim, great course. I like the way you explain "why" we would use Generics in real-world scenarios as opposed to just giving us "high-level" examples. Note that this teaching method sets you apart from other teachers. Also, you showed us an example where originally we don't use generics and then where (and why) we would use Generics (code reuse and decoupling logic implementation from actual data types).
Everyone on here has benefitted from Tim in one way or another. Please subscribe to this man's Patreon, even if it's just the $1, that's nothing compared to the value he provides us for FREE! Support this guy!!!
Agree. One of the best teachers that I've found so far. Really clear, in-depth, not going on too fast (like some others just rushing on), so it's easy to follow and grasp. Brilliant! Thanx a lot. :)
Adicted to IAmTimCorey channel. Learning makes easy when we find the right person who can answer our questions without asking them. You are a Great teacher and your efforts are really amazing. Thank you so much Sir. Love from India
Nice video as always Tim. Just a note on 35:20 for anyone interested in reflection: You can still grab the properties of a class, using reflection, without creating an instance of that class. This will compile and perform the same task: *var cols = typeof(T).GetProperties();* The instance was still needed in Tim's example though, since he's returning instances of that class in the Load method.
thanks a lot for this excellent and wonderful tutorial about generics. I made some changes on reflection parts and I would share with you guys: public static List LoadFromTextFile(string filePath) where T : class, new() { var lines = System.IO.File.ReadAllLines(filePath).ToList(); List outputList = new List();
var properties = typeof(T).GetProperties();
if (lines.Count < 2) throw new IndexOutOfRangeException("The file was either empty or missing."); // Splits the header into one column header per entry var headerColumns = lines[0].Split(','); lines.RemoveAt(0); foreach (var row in lines) { T entry = new T(); var rowValues = row.Split(','); foreach (var column in headerColumns.Select((columnName, columnIndex) => new { columnName, columnIndex })) { var propertyRef = properties.SingleOrDefault(property => property.Name == column.columnName); if (propertyRef != null) { object typedValue = Convert.ChangeType(rowValues[column.columnIndex], propertyRef.PropertyType); propertyRef.SetValue(entry, typedValue); } } outputList.Add(entry); } return outputList; } public static void SaveToTextFile(List lstData, string filePath) where T : class { List lines = new List(); if (!(lstData?.Count > 0)) throw new ArgumentNullException("data", "You must populate the data parameter with at least one value."); var properties = typeof(T).GetProperties(); lines.Add(string.Join(",", properties.Select(c => c.Name))); foreach (var row in lstData) { var rowValues = properties.Select(c => c.GetValue(row)).ToList(); lines.Add(string.Join(",", rowValues)); } System.IO.File.WriteAllLines(filePath, lines); }
what I iike about your tutorials like this one, is you don't over complicate things and I believe you always consider the level of skill of your watchers, explaining how and why things are done in a certain way. thanks Tim.
I have no idea how anyone could possibly give this video a thumbs down. Thanks Tim! You are awesome. I'll be heading over to Patreon real soon. Appreciate all you do to make our lives easier and wealthier!
Man been watching and liking all your vids. They are solid. As a person finishing up a year's worth of c# classes, I still find your way of teaching really easy to understand, and the tips and way in which you deliver information is extremely helpful. Many thanks buddy!
Well, thank you Tim for the great content you provide for free to us, the C# developers community. I have an old habit I took when learning C language, a long time ago when I was a student. I always put my checking code at the beginning of my methods, before any declaration or usage of variables and objects. So that I get rid of incorrect or incomplete values before going further, for instance by raising an exception or returning an error code. I don't know if it's a good practice, but I'm sure data is correct after that checking step.
Thank you for your videos, there are amazing. You help me so much to learn, and your sound and spelling is so clear to make it easy to understand for people that english isnt their native language.
You are so good sir, you explain it clearly. Even the topic is pretty advance for me, I can imagine things by your words. Thanks for making this video:)
Thanks again Tim for a great tutorial. I actually just used what I learned on a project where I have a method that calls a Web API and was returning JSON. Then I would deserialize it in the calling method into the proper type. Now I just use generics and this method returns the object that I called for. So much nicer. Old code... public static async Task SendRequest(HttpMethod method, string requestUri, object payload = null) which returned the raw JSON string New code. public static async Task SendRequest(HttpMethod method, string requestUri, object payload = null) where T : class which returns JsonConvert.DeserializeObject(responsePayload)
Excellent video, Generics have always been a bit confusing to me and it helps me best when there is a practical demo like in this video. So thanks for that
Hey Tim! I am a very big fan of your videos! Thank you for helping me learn C#! I was wondering if you plan to make a follow-up on generics and speak about how we can use generics and dependency inversion together as principles to make dynamic interfaces that we can reuse? I think it is a very interesting and challenging topic that most people would appreciate.
Your videos are clear and simple and I enjoy watching it. I've tried Pluralsight before and all of the teachers so far (like 4 people) were unnecessarily complicating stuff and were very formal and boring. Thanks a million Tim.
Great video and explanation. I have trouble learning a lot of advanced C# like this though. Even if i understand it i need to use it in practice multiple times to actually make it stick in my head. And when its things like this that has very rare use cases its very hard. You get a long way with the very basics of C#, and that can become a problem.
very very awesome , you are so great, yesterday i was creating method to write and read xml files and i couldn't make them generic, know i now why and thanks to you many many thanks
Thanks Tim for explaining the concept of Generics in simple terms. You could have also covered the complexity analysis in more detail while discussing the applied reflections. But You did explain it a little bit in terms of time I guess...
I have constant thoughts on how to improve every video. Part of that led me to make this video on balancing that desire for perfection - th-cam.com/video/b5TspWBQkMk/w-d-xo.html
good video. nice coverage of C# and basic file io as a bonus. generics can be confusing if newly introduced to the concept, but a good explanation overall.
Notes that i took: Generics are helpful to for example not create mutliple methods doing the same thing. Imagine having an array of type int, an array of type double and array of type string. If you'd want to print out the contents of these arrays, you would normally have to create three methods with three different parameters to display them. One with an int parameter etc. Instead, you can create a Generic Method. A Generic Method is created by putting " " at the end of the Method name. Then the parameter. Instead of putting a data type as a parameter, you can instead put "T" as a parameter and then call it three times with the different arrays. So instead of having 3 different Methods to call these three different arrays with different data types, you can create one generic method which accepts all data types. You can call your generic whatever you want, it doesnt have to be "T". ------------------------------------------------------ The T in generics specifies which type we are talking about.
Great tutorial. You could possibly optimise the code in the SaveToTextFile method by creating another method that loops through the columns and build the line without the trailing comma, as this code is duplicated.
the hardest way ever of explaining Generics why choose a very hard example to explain Generics why choose advance way (where T)if beginners like me dont know the simple way () not recommended for beginners
This is nearly a one-hour tutorial on the topic of generics. Maybe approach it as a course on generics rather than just a beginner's tutorial. The beginning (first 20 minutes or so) is the beginner tutorial. Then we go deeper from there.
life would have been better if those expensive books and college courses explain programming in this way. i believe generic classes would create the same effect and converting those methods to non static so that they can be instantiated please correct me if am wrong (apologies, i just saw you mentioned it at the end of the video :D)
In the load LoadTextFromFile function The that you pass in is a string, but then you say "Where T : class, new()". Wouldn't that "Where" statement require you to pass in something like a Person instance or LogEntry instance rather than a string?
You are such a great teacher. Many blessings to you. Simplicity is born out of a deeper understanding. Your tutorials are brilliant, like a breath of fresh air.
Thank you for the kind words.
I agree. Every lesson is very consistent which helps in the learning process.
"Simplicity is born out of a deeper understanding" .........deep
And yes, Tim Corey is the best
Glad you're still with us. Sounds like a crazy experience, that tsunami... Hopefully one day I will learn French or find a translated copy of your book. Interesting to see you coding!
And his voice as well 😍
the beauty of this channel is it shows the practical usage of the theoretical concept.
Thanks!
You're my fav C# instructor. Period! I don't know what moment or who sparked the idea in your head that you decided to share your knowledge with the world, I'm just grateful that you did :-)
Tim, great course.
I like the way you explain "why" we would use Generics in real-world scenarios as opposed to just giving us "high-level" examples. Note that this teaching method sets you apart from other teachers.
Also, you showed us an example where originally we don't use generics and then where (and why) we would use Generics (code reuse and decoupling logic implementation from actual data types).
I am glad you found it helpful.
I haven't come across a better teacher for C# programming online. Thank you so much for what you are doing!
You're very welcome!
I agree
Best C# generics tutorial I have come across. Thanks, Tim. Really appreciate it.
You are most welcome. Thanks for watching.
Good one. Restriction and mentioning empty constructor was new to me. Thank you
Thank you!
Everyone on here has benefitted from Tim in one way or another. Please subscribe to this man's Patreon, even if it's just the $1, that's nothing compared to the value he provides us for FREE! Support this guy!!!
I appreciate the kind words and the support.
Or sign up his courses to support him..
That is an excellent and simple explanation. I had some confusion about Generic methods, which are cleared now.
Thank you.
Glad it was helpful!
Tim, again, an older but very timeless video. Thanks for the clear explanation on generics!
You are welcome.
This is great. You concisely explained a concept that i originally perceived to be intimidating and confusing. Bravo
I am glad it was helpful.
Agree. One of the best teachers that I've found so far. Really clear, in-depth, not going on too fast (like some others just rushing on), so it's easy to follow and grasp. Brilliant! Thanx a lot. :)
You are most welcome. Thanks for watching.
Thank you Tim! This video improved my understanding of the use of generics.
Excellent!
Adicted to IAmTimCorey channel. Learning makes easy when we find the right person who can answer our questions without asking them. You are a Great teacher and your efforts are really amazing. Thank you so much Sir. Love from India
Thanks for trusting Tim with your time.
Best Video in Advance Topics Playlist up till now. I loved the generic methods because I faced this problem in my previous organization.
Glad it was helpful!
Nice video as always Tim. Just a note on 35:20 for anyone interested in reflection:
You can still grab the properties of a class, using reflection, without creating an instance of that class. This will compile and perform the same task: *var cols = typeof(T).GetProperties();*
The instance was still needed in Tim's example though, since he's returning instances of that class in the Load method.
Yep, thanks for pointing that out.
thanks a lot for this excellent and wonderful tutorial about generics.
I made some changes on reflection parts and I would share with you guys:
public static List LoadFromTextFile(string filePath) where T : class, new()
{
var lines = System.IO.File.ReadAllLines(filePath).ToList();
List outputList = new List();
var properties = typeof(T).GetProperties();
if (lines.Count < 2)
throw new IndexOutOfRangeException("The file was either empty or missing.");
// Splits the header into one column header per entry
var headerColumns = lines[0].Split(',');
lines.RemoveAt(0);
foreach (var row in lines)
{
T entry = new T();
var rowValues = row.Split(',');
foreach (var column in headerColumns.Select((columnName, columnIndex) => new { columnName, columnIndex }))
{
var propertyRef = properties.SingleOrDefault(property => property.Name == column.columnName);
if (propertyRef != null)
{
object typedValue = Convert.ChangeType(rowValues[column.columnIndex], propertyRef.PropertyType);
propertyRef.SetValue(entry, typedValue);
}
}
outputList.Add(entry);
}
return outputList;
}
public static void SaveToTextFile(List lstData, string filePath) where T : class
{
List lines = new List();
if (!(lstData?.Count > 0))
throw new ArgumentNullException("data", "You must populate the data parameter with at least one value.");
var properties = typeof(T).GetProperties();
lines.Add(string.Join(",", properties.Select(c => c.Name)));
foreach (var row in lstData)
{
var rowValues = properties.Select(c => c.GetValue(row)).ToList();
lines.Add(string.Join(",", rowValues));
}
System.IO.File.WriteAllLines(filePath, lines);
}
Thanks for sharing.
I have been using generics for a quite long time, but never managed to understand how to make one. you explained it very well.
Many thanks Tim Corey
Awesome! I'm glad I could add to your knowledge.
I learned generics before. But today I learned why and when I should use it. Thank you !
You are welcome.
what I iike about your tutorials like this one, is you don't over complicate things and I believe you always consider the level of skill of your watchers, explaining how and why things are done in a certain way. thanks Tim.
Glad you like them!
Thanks Tim for giving so much to the community.
You are welcome.
This is excellent and simple tutorial on C# generics. Thank you for your efforts and sharing your precious knowledge.
I am glad you enjoyed it.
Very clever example and code Tim. Just the right amount of complexity. Liked the reflection thrown in too. Thank you.
You are welcome.
I have no idea how anyone could possibly give this video a thumbs down. Thanks Tim! You are awesome. I'll be heading over to Patreon real soon. Appreciate all you do to make our lives easier and wealthier!
I appreciate the kind words.
Merci bien for your hard efforts to enlighten us Tim! You are an inspiration to start making a good code.
You are welcome.
Man been watching and liking all your vids. They are solid. As a person finishing up a year's worth of c# classes, I still find your way of teaching really easy to understand, and the tips and way in which you deliver information is extremely helpful. Many thanks buddy!
You are most welcome. Thanks for watching.
Well, thank you Tim for the great content you provide for free to us, the C# developers community. I have an old habit I took when learning C language, a long time ago when I was a student. I always put my checking code at the beginning of my methods, before any declaration or usage of variables and objects. So that I get rid of incorrect or incomplete values before going further, for instance by raising an exception or returning an error code. I don't know if it's a good practice, but I'm sure data is correct after that checking step.
Interesting, thanks for sharing that approach.
Thank you for your videos, there are amazing. You help me so much to learn, and your sound and spelling is so clear to make it easy to understand for people that english isnt their native language.
I am glad my content has been so helpful.
Finaly an example where this is actualy useful. Now I understand the whole thing much better. Thanks a lot!
You are welcome.
I've been working with .NET, and primarily C#, since before it was even publicly available and I still learn great things from your videos. Thank you!
You are most welcome. Thanks for watching.
You are so good sir, you explain it clearly. Even the topic is pretty advance for me, I can imagine things by your words. Thanks for making this video:)
You are welcome.
It was very helpful for me. Thank you Tim.
Glad it was helpful!
Great work Tim! Your syllable timing is perfect and I can run your video at 1.25 or 1.5 times and it still seems normal to my fast Brain.
Great to hear!
This opened my mind to a lot of things that Ive seen on your other videos but which I did not fully appreciate - until now
Excellent!
Tim, 12,114 views and 418 likes and "0" dislikes as on date, That speaks quality of this video. :)
Thank you.
It's really helpful. Sir, only with your video did I learn why, I have to use generic. Thanks a lot.
Great!
Thanks again Tim for a great tutorial. I actually just used what I learned on a project where I have a method that calls a Web API and was returning JSON. Then I would deserialize it in the calling method into the proper type. Now I just use generics and this method returns the object that I called for. So much nicer.
Old code...
public static async Task SendRequest(HttpMethod method, string requestUri, object payload = null)
which returned the raw JSON string
New code.
public static async Task SendRequest(HttpMethod method, string requestUri, object payload = null) where T : class
which returns JsonConvert.DeserializeObject(responsePayload)
Great! I am glad it was so useful.
Wonderful content Tim. Kudos to you!
Thank you!
Excellent video, Generics have always been a bit confusing to me and it helps me best when there is a practical demo like in this video. So thanks for that
You are welcome.
Heh, I needed 6 minutes of Your video to understand what I need.
Truly great content.
Thanks!
Great material, bravo Tim!
Thank you!
Yes, Generic is useful, it can reduce duplicate code. Thank you very much. Very precise explanation.
You are welcome!
Very helpful, thank you.
You are welcome.
Thank you. Very informative. Very well explained.
You are welcome.
You're my hero Timmy
Such an emotional video, you killed off Sue Storm :)
It was a rough one, but don't forget, Sue is a comic book character. They never really die.
Good job! I appreciate you posting your videos.
Thanks!
That you very much. Has really improved my understanding regarding this topic. You are an excellet teacher
Awesome! I'm glad you were able to increase your understanding of the topic.
Great explanation, greetings from Argentina
Thank you!
Great example, very useful. Thanks a lot
You are welcome.
Thank you Tim! I work at company where we use C# and MVVM pattern, I learned some new things from you. :)
Excellent!
Great job!
Thanks!
I had a light-bulb moment when you showed the reason why not to use ArrayLists. Suddenly everything made sense. Thanks Tim.
Excellent!
Appealing tutorial.
Thanks!
28:27 "I was tired at 4:29 AM", me too, Tim, me too...
lol
Best tutorials on C#! Keep going!
Awesome! Will do.
am impressed, i wanna do more generics with different class properties.
Great!
Here is my “like”, Tim. Thanks for the great lesson.
You are most welcome. Thanks for watching.
Another great video clearly explaining an area that is often misunderstood!
Thank you!
Hey Tim! I am a very big fan of your videos! Thank you for helping me learn C#!
I was wondering if you plan to make a follow-up on generics and speak about how we can use generics and dependency inversion together as principles to make dynamic interfaces that we can reuse?
I think it is a very interesting and challenging topic that most people would appreciate.
Added to the list, thanks.
this is the best tuts, very clear
I am glad my content is helpful to you.
Your videos are clear and simple and I enjoy watching it. I've tried Pluralsight before and all of the teachers so far (like 4 people) were unnecessarily complicating stuff and were very formal and boring. Thanks a million Tim.
I appreciate the kind words.
She glad I found this channel!! Thank you Tim!
We are pleased you did also.
Perfect explanation. Thanks.
I'm glad.
Great lesson, Tim. You've done a great jog teaching us how to handle with C# technology, Thank you so much.
You are welcome.
Great effort put by creator
Thanks!
I just whatch your video about interfaces and now generics , We can have a lot fun mixing these two consepts
Yes we can.
Bow to the king.
I'm glad you enjoyed it.
Great video and explanation. I have trouble learning a lot of advanced C# like this though. Even if i understand it i need to use it in practice multiple times to actually make it stick in my head. And when its things like this that has very rare use cases its very hard. You get a long way with the very basics of C#, and that can become a problem.
Practice is definitely important. The more you practice it, the more you will grasp it.
very very awesome , you are so great, yesterday i was creating method to write and read xml files and i couldn't make them generic, know i now why and thanks to you
many many thanks
Great!
Thank you Tim
You are welcome.
Thankfull for all of your video sir.
You are welcome.
Thanks Tim for explaining the concept of Generics in simple terms. You could have also covered the complexity analysis in more detail while discussing the applied reflections. But You did explain it a little bit in terms of time I guess...
I have constant thoughts on how to improve every video. Part of that led me to make this video on balancing that desire for perfection - th-cam.com/video/b5TspWBQkMk/w-d-xo.html
amazing explaining
Thank you!
Your videos are insanely good. Love it.
Thank you!
You are that perfect c# book I was looking for!
Great!
you are a great tutor , thank you again and again for these videos
You are welcome.
good video. nice coverage of C# and basic file io as a bonus. generics can be confusing if newly introduced to the concept, but a good explanation overall.
Thanks for sharing!
Awesome! What a great lesson. Thank you.
You are welcome.
Notes that i took:
Generics are helpful to for example not create mutliple methods doing the same thing.
Imagine having an array of type int, an array of type double and array of type string.
If you'd want to print out the contents of these arrays, you would normally have to create three methods with three different parameters to display them. One with an int parameter etc.
Instead, you can create a Generic Method.
A Generic Method is created by putting " " at the end of the Method name. Then the parameter.
Instead of putting a data type as a parameter, you can instead put "T" as a parameter and then call it three times with the different arrays.
So instead of having 3 different Methods to call these three different arrays with different data types, you can create one generic method which accepts all data types.
You can call your generic whatever you want, it doesnt have to be "T".
------------------------------------------------------
The T in generics specifies which type we are talking about.
I'm glad you were following along.
Thank you so much sir! That was a very clean explanation and a brilliant example! Now I understood.
Thank you very much. I love this channel and found it very useful. I also love your way of teaching.
You are most welcome.
Great video. Thanks a lot.
Thanks for watching and trusting Tim to help expand your skills
Thank you for this video
You are welcome.
Thanks for the great lesson Tim!
My pleasure!
Thanks a lot, great example! You've got to love it!
Glad you like it!
In India today (5th September) we are celebrating Teachers day. And for me, you are one of the best teachers I came across.
Happy Teachers Day Tim!!
Thank you!
thank you. really clear.
You're welcome!
Excellent!
Thanks!
Recently, I watched your content aboute interface. It's make understand it more details. Thanks for your information and great example 😊
You're very welcome!
Great video. You really know how to explain things
Thank you.
Great tutorial. You could possibly optimise the code in the SaveToTextFile method by creating another method that loops through the columns and build the line without the trailing comma, as this code is duplicated.
Thanks alot for great videos and channel
You are welcome.
Thank you sir
You are welcome.
This is my 2nd favorite video you've made. :-)
Awesome! What's the first?
Very good videos !!
Thanks!
Nice explanation, thanks
You are welcome.
Köszönjük!
Thank you!
the hardest way ever of explaining Generics why choose a very hard example to explain Generics why choose advance way (where T)if beginners like me dont know the simple way () not recommended for beginners
This is nearly a one-hour tutorial on the topic of generics. Maybe approach it as a course on generics rather than just a beginner's tutorial. The beginning (first 20 minutes or so) is the beginner tutorial. Then we go deeper from there.
life would have been better if those expensive books and college courses explain programming in this way. i believe generic classes would create the same effect and converting those methods to non static so that they can be instantiated please correct me if am wrong (apologies, i just saw you mentioned it at the end of the video :D)
Glad I could answer your question by the end.
Pre-C19 Goals: Buy new Gaming Desktop.
Quarantine Goals: Buy Tim Corey courses.
It has changed a lot of priorities.
In the load LoadTextFromFile function The that you pass in is a string, but then you say "Where T : class, new()". Wouldn't that "Where" statement require you to pass in something like a Person instance or LogEntry instance rather than a string?