public int CalculateElapsedDays(DateTime from)
{
DateTime now = DateTime.Now;
return (now - from).Days;
} public static int CalculateElapsedDays(DateTime from, DateTime now) => (now - from).Days;
public int Divide(int numerator, int denominator)
{
return numerator / denominator;
} var result = Divide(1,0);
public static int Divide(int numerator, NonZeroInt denominator)
{
return numerator / denominator.Value;
} Func<int, bool> isMod2 = x => x % 2 == 0; var list = Enumerable.Range(1, 10); var evenNumbers = list.Where(isMod2);
public static IEnumerable<T> Where<T>(this IEnumerable<T> ts, Func<T, bool> predicate)
{
foreach (T t in ts)
if (predicate(t))
yield return t;
} 
@DatabaseTable(tableName = "users")
public class User {
@DatabaseField(id = true)
private String username;
@DatabaseField
private String password;
public User() {
// ORMLite needs a no-arg constructor
}
public User(String username, String password) {
this.username = username;
this.password = password;
}
// Implementing getter and setter methods
public String getUserame() {
return this.username;
}
public void setName(String username) {
this.username = username;
}
public String getPassword() {
return this.password;
}
public void setPassword(String password) {
this.password = password;
}
} <meta-data android:name="DATABASE" android:value="my_database.db" /> <meta-data android:name="VERSION" android:value="1" /> <meta-data android:name="QUERY_LOG" android:value="true" /> <meta-data android:name="DOMAIN_PACKAGE_NAME" android:value="com.my-domain" />
public class User extends SugarRecord<User> {
String username;
String password;
int age;
@Ignore
String bio; //this will be ignored by SugarORM
public User() { }
public User(String username, String password,int age){
this.username = username;
this.password = password;
this.age = age;
}
} User johndoe = new User(getContext(),"john.doe","secret",19);
johndoe.save(); //ذخیره کاربر جدید در دیتابیس
//حذف تمامی کاربرانی که سنشان 19 سال است
List<User> nineteens = User.find(User.class,"age = ?",new int[]{19});
foreach(user in nineteens) {
user.delete();
} 
<meta-data android:name="AA_DB_NAME" android:value="my_database.db" /> <meta-data android:name="AA_DB_VERSION" android:value="1" />
public class MyActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ActiveAndroid.initialize(this);
//ادامه برنامه
}
} @Table(name = "User")
public class User extends Model {
@Column(name = "username")
public String username;
@Column(name = "password")
public String password;
public User() {
super();
}
public User(String username,String password) {
super();
this.username = username;
this.password = password;
}
} <meta-data android:name="ormdroid.database.name" android:value="your_database_name" /> <meta-data android:name="ormdroid.database.visibility" android:value="PRIVATE||WORLD_READABLE||WORLD_WRITEABLE" />
ORMDroidApplication.initialize(someContext);
public class Person extends Entity {
public int id;
public String name;
public String telephone;
}
//====================
Person p = Entity.query(Person.class).where("id=1").execute();
p.telephone = "555-1234";
p.save();
// یا
Person person = Entity.query(Person.class).where(eql("id", id)).execute();
p.telephone = "555-1234";
p.save(); بسیاری از نقاط دنیا در حد کد پستی توسط گوگل ایندکس شده اند با استفاده از این تکنیک میتوان آدرس پستی نقطه مورد نظر را بدست آورد .
«... پرسشنامه زیر توسط جمعی از توسعه دهنده‌ها و برنامه نویس‌های ایرانی تهیه شده تا با نظر سنجی از بقیه توسعه دهنده‌ها و به دست آوردن مجموعه ای از اطلاعات فان در کنار اطلاعات مفید، کمکی باشه برای انتخاب بهتر شغل و چانه‌زنی‌های مرتبط و هدفگذاری‌های آینده. پرسشنامه به شکل کاملا بی نام پر میشه و فقط اندازه و شکل شرکت پرسیده میشه تا بتونیم درک دقیق‌تری از وضعیت بازار کار مون داشته باشیم ...»
/// <summary>
/// دستور العمل
/// </summary>
class Recipe
{
public int Id { get; set; }
public string Name { get; set; }
}
/// <summary>
/// بازخورد
/// </summary>
class Review
{
public int RecipeId { get; set; }
public string ReviewText { get; set; }
} Recipe[] recipes =
{
new Recipe {Id = 1, Name = "Mashed Potato"},
new Recipe {Id = 2, Name = "Crispy Duck"},
new Recipe {Id = 3, Name = "Sachertorte"}
};
Review[] reviews =
{
new Review {RecipeId = 1, ReviewText = "Tasty!"},
new Review {RecipeId = 1, ReviewText = "Not nice :("},
new Review {RecipeId = 1, ReviewText = "Pretty good"},
new Review {RecipeId = 2, ReviewText = "Too hard"},
new Review {RecipeId = 2, ReviewText = "Loved it"}
};
var query = from recipe in recipes
join review in reviews on recipe.Id equals review.RecipeId
select new //anonymous type
{
RecipeName = recipe.Name,
RecipeReview = review.ReviewText
};
foreach (var item in query)
{
Console.WriteLine($"{item.RecipeName}-{item.RecipeReview}");
} Mashed Potato-Tasty! Mashed Potato-Not nice :( Mashed Potato-Pretty good Crispy Duck-Too hard Crispy Duck-Loved it
var query = from recipe in recipes
join review in reviews on recipe.Id equals review.RecipeId
into reviewGroup
select new //anonymous type
{
RecipeName = recipe.Name,
Reviews = reviewGroup//collection of related reviews
};
foreach (var item in query)
{
Console.WriteLine($"Review for {item.RecipeName}");
foreach (var review in item.Reviews)
{
Console.WriteLine($"-{review.ReviewText}");
}
} Review for Mashed Potato -Tasty! -Not nice :( -Pretty good Review for Crispy Duck -Too hard -Loved it Review for Sachertorte
var query = from recipe in recipes
join review in reviews on recipe.Id equals review.RecipeId
into reviewGroup
from rg in reviewGroup.DefaultIfEmpty()
select new //anonymous type
{
RecipeName = recipe.Name,
//RecipeReview = rg.ReviewText SystemNullException
RecipeReview = (rg == null ? "n/a" : rg.ReviewText)
};
foreach (var item in query)
{
Console.WriteLine($"{item.RecipeName}-{item.RecipeReview}");
} Mashed Potato-Tasty! Mashed Potato-Not nice :( Mashed Potato-Pretty good Crispy Duck-Too hard Crispy Duck-Loved it Sachertorte-n/a
var query = from recipe in recipes
join review in reviews on recipe.Id equals review.RecipeId
into reviewGroup
from rg in reviewGroup.DefaultIfEmpty(new Review { ReviewText = "N/A" })
select new //anonymous type
{
RecipeName = recipe.Name,
RecipeReview = rg.ReviewText
};
foreach (var item in query)
{
Console.WriteLine($"{item.RecipeName}-{item.RecipeReview}");
} Mashed Potato-Tasty! Mashed Potato-Not nice :( Mashed Potato-Pretty good Crispy Duck-Too hard Crispy Duck-Loved it Sachertorte-N/A
PM> install-package AutoMapper PM> install-package EntityFramework
public class BlogPost
{
public int Id { get; set; }
public string Title { get; set; }
public string Content { get; set; }
[ForeignKey("UserId")]
public virtual User User { get; set; }
public int UserId { get; set; }
}
public class User
{
public int Id { get; set; }
public string Name { get; set; }
public int Age { get; set; }
public virtual ICollection<BlogPost> BlogPosts { get; set; }
} public class UserViewModel
{
public int Id { set; get; }
public string Name { set; get; }
public ICollection<BlogPost> BlogPosts { get; set; }
} public class TestProfile : Profile
{
protected override void Configure()
{
this.CreateMap<User, UserViewModel>();
}
public override string ProfileName
{
get { return this.GetType().Name; }
}
} Mapper.Initialize(cfg => // In Application_Start()
{
cfg.AddProfile<TestProfile>();
}); using (var context = new MyContext())
{
var user1 = context.Users.FirstOrDefault();
if (user1 != null)
{
var uiUser = new UserViewModel();
Mapper.Map(source: user1, destination: uiUser);
Console.WriteLine(uiUser.Name);
foreach (var post in uiUser.BlogPosts)
{
Console.WriteLine(post.Title);
}
}
} var user1 = context.Users.Include(user => user.BlogPosts).FirstOrDefault();
var uiUser = context.Users.Project().To<UserViewModel>().FirstOrDefault();
