Spawn an Online Game with Blazor, .NET 7 and Clean Architecture in under 60 minutes
In this fun talk, Luke Parker will show you step-by-step how to build a playable game in under 60 minutes. He will go over some basic game design, project planning, then build the game and finally… play live with the audience! Utilizing code sharing and the magic of Clean Architecture allows for very rapid app development. Also, leveraging MudBlazor as the component library lets you save time and to focus on what really matters.
I commonly hear the phrase “The web application worked in the pre-production environment and now is encountering issues in production and the server’s configuration are identical!” when I appear onsite to help assist with the resolution of the issues. Upon further investigation, an IIS module has not been installed on the production server, or the configuration is different for an application pool setting between the pre-production and production environments. This is a very common scenario I encounter in the field and here are some suggestions on how to determine differences between IIS servers in an IIS farm environment or between servers in different environments, such as pre-production and production. Keeping server configuration and content synchronized is always a challenge and I hope these suggestions help out.
زمانی که سیستم عامل های GUI مثل ویندوز به بازار آمدند، یکی از قسمت‌های گرافیکی آن‌ها AddressBar نام داشت که مسیر حرکت آن‌ها را در فایل سیستم نشان میداد و در سیستم عامل‌های متنی CLI با دستور cd یا pwd انجام می‌شد. بعدها در وب هم همین حرکت با نام BreadCrumb صورت گرفت که به عنوان مثال مسیر رسیدن به صفحه‌ی یک محصول یا یک مقاله را نشان میداد. در یک پروژه‌ی اندرویدی نیاز بود تا یک ساختار درختی را پیاده سازی کنم، ولی در برنامه‌های اندروید ایجاد یک درخت، کار هوشمندانه و مطلوبی نیست و روش کار به این صورت است که یک لیست از گروه‌های والد را نمایش داده و با انتخاب هر آیتم لیست به آیتم‌های فرزند تغییر میکند. حالا مسئله این بود که کاربر باید مسیر حرکت خودش را بشناسد. به همین علت مجبور شدم یک BreadCrumb را برای آن طراحی کنم که در زیر تصویر آن را مشاهده می‌کنید.
از نکات جالب توجه در مورد این ماژول میتوان گفت که قابلیت این را دارد تا تصمیمات خود را بر اساس اندازه‌های مختلف صفحه نمایش بگیرد. به عنوان مثال اگر آیتم‌های بالا بیشتر از سه عدد باشد و در صفحه جا نشود از یک مسیر جعلی استفاده میکند و همه‌ی آیتم‌ها با اندیس شماره 1 تا index-3 را درون یک آیتم با عنوان (...) قرار می‌دهد که من به آن می‌گویم مسیر جعلی. به عنوان نمونه مسیر تصویر بالا در صفحه جا شده است و نیازی به این کار دیده نشده است. ولی تصویر زیر از آن جا که مسیر، طول width صفحه نمایش رد کرده است، نیاز است تا چنین کاری انجام شود. موقعی‌که کاربر آیتم ... را کلیک کند، مسیر باز شده و به محل index-3 حرکت میکند. یعنی دو مرحله به عقب باز می‌گردد.
نگاهی به کارکرد ماژول
قبل از توضیح در مورد سورس، اجازه دهید نحوه‌ی استفاده از آن را ببینیم.
این سورس شامل دو کلاس است که ساده‌ترین کلاس آن AndBreadCrumbItem می‌باشد که مشابه کلاس ListItem در بخش وب دات نت است و دو مقدار، یکی متن و دیگری Id را می‌گیرد:
سورس:
public class AndBreadCrumbItem {
private int Id;
private String diplayText;
public AndBreadCrumbItem(int Id, String displayText)
{
this.Id=Id;
this.diplayText=displayText;
}
public String getDiplayText() {
return diplayText;
}
public void setDiplayText(String diplayText) {
this.diplayText = diplayText;
}
public int getId() {
return Id;
}
public void setId(int id) {
Id = id;
}
} به عنوان مثال می‌خواهیم یک breadcrumb را با مشخصات زیر بسازیم:
AndBreadCrumbItem itemhome=new AndBreadCrumbItem(0,"Home"); AndBreadCrumbItem itemproducts=new AndBreadCrumbItem(12,"Products"); AndBreadCrumbItem itemdigital=new AndBreadCrumbItem(15,"Digital"); AndBreadCrumbItem itemhdd=new AndBreadCrumbItem(56,"Hard Disk Drive");
AndBreadCrumb breadCrumb=new AndBreadCrumb(this);
breadCrumb.AddNewItem(itemhome);
breadCrumb.AddNewItem(itemproducts);
breadCrumb.AddNewItem(itemdigital);
breadCrumb.AddNewItem(itemhdd); breadCumb.setContext(this);
پس از افزودن آیتم ها، تنظیمات زیر را اعمال نمایید:
LinearLayout layout=(LinearLayout)getActivity().findViewById(R.id.breadcumblayout);
layout.setPadding(8, 8, 8, 8);
breadCrumb.setLayout(layout);
breadCrumb.SetTinyNextNodeImage(R.drawable.arrow);
breadCrumb.setTextSize(25);
breadCrumb.SetViewStyleId(R.drawable.list_item_style); breadCrumb.UpdatePath();
breadCrumb.setRTL(true);
در صورتیکه قصد دارید تنظیمات بیشتری چون رنگ متن، فونت متن و ... را روی هر المان اعمال کنید، از رویداد زیر استفاده کنید:
breadCrumb.setOnTextViewUpdate(new ITextViewUpdate() {
@Override
public TextView UpdateTextView(Context context, TextView tv) {
tv.setTextColor(...);
tv.setTypeface(...);
return tv;
}
}); breadCumb.setOnClickListener(new IClickListener() {
@Override
public void onClick(int position, int Id) {
//...
}
}); آخرین متد موجود که کمترین استفاده را دارد، متد SetNoResize است. در صورتیکه این متد با True مقداردهی گردد، عملیات تنظیم بر اساس صفحه‌ی نمایش لغو می‌شود. این متد برای زمانی مناسب است که به عنوان مثال شما از یک HorozinalScrollView استفاده کرده باشید. در این حالت layout شما هیچ گاه به پایان نمی‌رسد و بهتر هست عملیات اضافه را لغو کنید.
نگاهی به سورس
کلاس زیر شامل بخش‌های زیر است:
//=-=--=-=-=-=-=-=-=-=-=-=-=- Private Properties -=-=-=-=-=-=-=--=-=-=
private List<AndBreadCrumbItem> items=null;
private List<TextView> textViews;
private int tinyNextNodeImage;
private int viewStyleId;
private Context context;
private boolean RTL;
private float textSize=20;
private boolean noResize=false;
LinearLayout layout;
IClickListener clickListener;
ITextViewUpdate textViewUpdate;
LinearLayout.LayoutParams params ; //=-=---=-=-=-=-- Constructor =--=-=-=-=-=--=-=-
public AndBreadCrumb(Context context)
{
this.context=context;
params = new LinearLayout.LayoutParams
(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
}
//=-=-=--=--=-=-=-=-=-=-=-=- Public Properties --=-=-=-=-=-=--=-=-=-=-=-=-
//each category would be added to create path
public void AddNewItem(AndBreadCrumbItem item)
{
if(items==null)
items=new ArrayList<>();
items.add(item);
}
// if you want a pointer or next node between categories or textviews
public void SetTinyNextNodeImage(int resId) {this.tinyNextNodeImage=resId;}
public void SetViewStyleId(int resId) {this.viewStyleId=resId;}
public void setTextSize(float textSize) {this.textSize = textSize;}
public boolean isRTL() {
return RTL;
}
public void setRTL(boolean RTL) {
this.RTL = RTL;
}
public void setLayout(LinearLayout layout) {
this.layout = layout;
}
public void setContext(Context context) {
this.context = context;
}
public boolean isNoResize() {
return noResize;
}
public void setNoResize(boolean noResize) {
this.noResize = noResize;
} //primary method for render objects on layout
private void DrawPath() {
//stop here if essentail elements aren't present
if (items == null) return ;
if (layout == null) return;
if (items.size() == 0) return;
//we need to get size of layout,so we use the post method to run this thread when ui is ready
layout.post(new Runnable() {
@Override
public void run() {
//textviews created here one by one
int position = 0;
textViews = new ArrayList<>();
for (AndBreadCrumbItem item : items) {
TextView tv = MakeTextView(position, item.getId());
tv.setText(item.getDiplayText());
textViews.add(tv);
position++;
}
//add textviews on layout
AddTextViewsOnLayout();
//we dont manage resizing anymore
if(isNoResize()) return;
//run this code after textviews Added to get widths of them
TextView last_tv=textViews.get(textViews.size()-1);
last_tv.post(new Runnable() {
@Override
public void run() {
//define width of each textview depend on screen width
BatchSizeOperation();
}
});
}
});
} TextView tv=new TextView(this); tv.getWidth(); //return 0 layout.add(tv); tv.getWidth(); //return 0
TextView tv=new TextView(this);
tv.post(new Runnable() {
@Override
public void run() {
tv.getWidth(); //return x
}
}); private TextView MakeTextView(final int position, final int Id)
{
//settings for cumbs
TextView tv=new TextView(this.context);
tv.setEllipsize(TextUtils.TruncateAt.END);
tv.setSingleLine(true);
tv.setTextSize(TypedValue.COMPLEX_UNIT_PX, textSize);
tv.setBackgroundResource(viewStyleId);
/*call custom event - this event will be fired when user click on one of
textviews and returns position of textview and value that user sat as id
*/
tv.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
SetPosition(position);
clickListener.onClick(position, Id);
}
});
//if user wants to update each textviews
if(textViewUpdate!=null)
tv=textViewUpdate.UpdateTextView(context,tv);
if(isRTL())
tv.setRotationY(180);
return tv;
} //this method calling by everywhere to needs add textviews on the layout like master method :drawpath
private void AddTextViewsOnLayout()
{
//prepare layout
//remove everything on layout for recreate it
layout.removeAllViews();
layout.setOrientation(LinearLayout.HORIZONTAL);
layout.setVerticalGravity(Gravity.CENTER_VERTICAL);
if(isRTL())
layout.setRotationY(180);
//add textviews one by one
int position=0;
for (TextView tv:textViews)
{
layout.addView(tv,params);
//add next node image between textviews if user defined a next node image
if(tinyNextNodeImage>0)
if(position<(textViews.size()-1)) {
layout.addView(GetNodeImage(), params);
position++;
}
}
} //set textview width depend on screen width
private void BatchSizeOperation()
{
//get width of next node between cumbs
Bitmap tinyBmap = BitmapFactory.decodeResource(context.getResources(), tinyNextNodeImage);
int tinysize=tinyBmap.getWidth();
//get sum of nodes
tinysize*=(textViews.size()-1);
...
} //get width size of screen(layout is screen here)
int screenWidth=GetLayoutWidthSize();
//get sum of arrows and cumbs width
int sumtvs=tinysize;
for (TextView tv : textViews) {
int width=tv.getWidth();
sumtvs += width;
} private int GetLayoutWidthSize()
{
int width=layout.getWidth();
int padding=layout.getPaddingLeft()+layout.getPaddingRight();
width-=padding;
return width;
} private void BatchSizeOperation()
{
....
//if sum of cumbs is less than screen size the state is good so return same old textviews
if(sumtvs<screenWidth)
return ;
if(textViews.size()>3)
{
//make fake path
MakeFakePath();
//clear layout and add textviews again
AddTextViewsOnLayout();
}
//get free space without next nodes -> and spilt rest of space to textviews count to get space for each textview
int freespace =screenWidth-tinysize;
int each_width=freespace/textViews.size();
//some elements have less than each_width,so we should leave size them and calculate more space again
int view_count=0;
for (TextView tv:textViews)
{
if (tv.getWidth()<=each_width)
freespace=freespace-tv.getWidth();
else
view_count++;
}
if (view_count==0) return;
each_width=freespace/view_count;
for (TextView tv:textViews)
{
if (tv.getWidth()>each_width)
tv.setWidth(each_width);
}
} //if elements are so much(mor than 3),we make a fake path to decrease elements
private void MakeFakePath()
{
//we make 4 new elements that index 1 is fake element and has a rest of real path in its heart
//when user click on it,path would be opened
textViews=new ArrayList<>(4);
TextView[] tvs=new TextView[4];
int[] positions= {0,items.size()-3,items.size()-2,items.size()-1};
for (int i=0;i<4;i++)
{
//request for new textviews
tvs[i]=MakeTextView(positions[i],items.get(positions[i]).getId());
if(i!=1)
tvs[i].setText(items.get(positions[i]).getDiplayText());
else {
tvs[i].setText("...");
//override click event and change it to part of code to open real path by call setposition method and redraw path
tvs[i].setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int pos = items.size() - 3;
int id = items.get(pos).getId();
SetPosition(items.size() - 3);
clickListener.onClick(pos, id);
}
});
}
textViews.add(tvs[i]);
}
} We just published eShopSupport, a .NET sample app that brings AI into the world of eShop. Includes examples of summarisation, classification, semantic search, and a Q&A bot (including local models). It’s the demo app we used in talks such as
Jon Skeet presents some of the features coming in C# 7 - tuples, pattern matching, local functions, throw expressions, numeric literals, and more – along with hints regarding future versions.
/*
* Password Hashing With PBKDF2 (http://crackstation.net/hashing-security.htm).
* Copyright (c) 2013, Taylor Hornby
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
using System;
using System.Text;
using System.Security.Cryptography;
namespace PasswordHash
{
/// <summary>
/// Salted password hashing with PBKDF2-SHA1.
/// Author: havoc AT defuse.ca
/// www: http://crackstation.net/hashing-security.htm
/// Compatibility: .NET 3.0 and later.
/// </summary>
public class PasswordHash
{
// The following constants may be changed without breaking existing hashes.
public const int SALT_BYTE_SIZE = 24;
public const int HASH_BYTE_SIZE = 24;
public const int PBKDF2_ITERATIONS = 1000;
public const int ITERATION_INDEX = 0;
public const int SALT_INDEX = 1;
public const int PBKDF2_INDEX = 2;
/// <summary>
/// Creates a salted PBKDF2 hash of the password.
/// </summary>
/// <param name="password">The password to hash.</param>
/// <returns>The hash of the password.</returns>
public static string CreateHash(string password)
{
// Generate a random salt
RNGCryptoServiceProvider csprng = new RNGCryptoServiceProvider();
byte[] salt = new byte[SALT_BYTE_SIZE];
csprng.GetBytes(salt);
// Hash the password and encode the parameters
byte[] hash = PBKDF2(password, salt, PBKDF2_ITERATIONS, HASH_BYTE_SIZE);
return PBKDF2_ITERATIONS + ":" +
Convert.ToBase64String(salt) + ":" +
Convert.ToBase64String(hash);
}
/// <summary>
/// Validates a password given a hash of the correct one.
/// </summary>
/// <param name="password">The password to check.</param>
/// <param name="correctHash">A hash of the correct password.</param>
/// <returns>True if the password is correct. False otherwise.</returns>
public static bool ValidatePassword(string password, string correctHash)
{
// Extract the parameters from the hash
char[] delimiter = { ':' };
string[] split = correctHash.Split(delimiter);
int iterations = Int32.Parse(split[ITERATION_INDEX]);
byte[] salt = Convert.FromBase64String(split[SALT_INDEX]);
byte[] hash = Convert.FromBase64String(split[PBKDF2_INDEX]);
byte[] testHash = PBKDF2(password, salt, iterations, hash.Length);
return SlowEquals(hash, testHash);
}
/// <summary>
/// Compares two byte arrays in length-constant time. This comparison
/// method is used so that password hashes cannot be extracted from
/// on-line systems using a timing attack and then attacked off-line.
/// </summary>
/// <param name="a">The first byte array.</param>
/// <param name="b">The second byte array.</param>
/// <returns>True if both byte arrays are equal. False otherwise.</returns>
private static bool SlowEquals(byte[] a, byte[] b)
{
uint diff = (uint)a.Length ^ (uint)b.Length;
for (int i = 0; i < a.Length && i < b.Length; i++)
diff |= (uint)(a[i] ^ b[i]);
return diff == 0;
}
/// <summary>
/// Computes the PBKDF2-SHA1 hash of a password.
/// </summary>
/// <param name="password">The password to hash.</param>
/// <param name="salt">The salt.</param>
/// <param name="iterations">The PBKDF2 iteration count.</param>
/// <param name="outputBytes">The length of the hash to generate, in bytes.</param>
/// <returns>A hash of the password.</returns>
private static byte[] PBKDF2(string password, byte[] salt, int iterations, int outputBytes)
{
Rfc2898DeriveBytes pbkdf2 = new Rfc2898DeriveBytes(password, salt);
pbkdf2.IterationCount = iterations;
return pbkdf2.GetBytes(outputBytes);
}
}
} Missing Features in Entity Framework Core
Here’s a brief summary of some of the features that were present in previous versions of Entity Framework (6.x) and were excluded (or are not yet implemented) in Entity Framework Core 2.0:
