c#-3.0

问题 Please suggest me where i need to update/refactor the code to get rid of exception. I am getting exception while I try to decrypt the encrypted string using following code. Following line is throwing exception using (StreamReader srDecrypt = new StreamReader(csDecrypt)) { // Read the decrypted bytes from the decrypting stream // and place them in a string. plaintext = srDecrypt.ReadToEnd(); } public string EncryptAuthenticationTokenAes(string plainText) { byte[] encrypted; // Create an

问题 I want to change image to Black-White or Sepia. After converting the image i want to replace the existing image with the converted image. Please give me some suggestion. 回答1: There are many ways to desaturate a color image. In fact, there is probably no one "true" or "correct" way to do it, though some ways are more "correct" than others. I assume that your image is in RGB (Red-Green-Blue) format (though BGR is also common). The simplest way, which should work for most photos (but less so for

问题 The => token is part of the C# 3.0 lambda syntax. My efforts to find the name of this token have failed so far. 回答1: Lambda operator 回答2: What it is called, in terms of how to pronounce it when reading code, is covered by Eric Lippert in Reading Code Over the Telephone. 回答3: It's referred to as the 'goes to' operator. 回答4: Turns out the answer depends on the context: c=>c+1 c goes to c plus one (Customer c)=>c.Name customer c becomes c dot name (Customer c)=>c.Age > 21 customer c such that c

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 2 years ago . How do I use SQL in memory database in .Net?? How does an in-memory database work? 回答1: In-Memory Database (IMDB) is a memory-resident relational database that eliminates disk access by storing and manipulating data in main memory. An IMDB usually features a strict memory-based

问题 I'm a bit confused on the point of Automatic properties in C# e.g public string Forename{ get; set; } I get that you are saving code by not having to declare a private variable, but what's the point of a property when you are not using any get or set logic? Why not just use public string Forename; I'm not sure what the difference between these 2 statements is, I always thought you used properties if you wanted additional get/set logic? 回答1: Properties can have code put into them without

问题 Is it possible to add different type of generic objects to a list?. As below. public class ValuePair<T> { public string Name { get; set;} public T Value { get; set; } and let say I have all these objects... ValuePair<string> data1 = new ValuePair<string>(); ValuePair<double> data2 = new ValuePair<double>(); ValuePair<int> data3 = new ValuePair<int>(); I would like to hold these objects in a generic list.such as List<ValuePair> list = new List<ValuePair>(); list.Add(data1); list.Add(data2);

问题 In C#, the properties of anonymous types are read-only: var person = new { Surname = "Smith", OtherNames = "John" }; person.Surname = "Johnson"; // ERROR: .Surname is read-only Of course I can declare a real class if I want writable fields or properties, but regardless, what is the reasoning behind this design decision to make the properties read-only? 回答1: Interesting article on that here. From there ... ... [B]y ensuring that the members do not change, we ensure that the hash is constant

问题 In C#, the properties of anonymous types are read-only: var person = new { Surname = "Smith", OtherNames = "John" }; person.Surname = "Johnson"; // ERROR: .Surname is read-only Of course I can declare a real class if I want writable fields or properties, but regardless, what is the reasoning behind this design decision to make the properties read-only? 回答1: Interesting article on that here. From there ... ... [B]y ensuring that the members do not change, we ensure that the hash is constant

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 8 years ago . Locked . This question and its answers are locked because the question is off-topic but has historical significance. It is not

问题 Take the method System.Windows.Forms.Control.Invoke(Delegate method) Why does this give a compile time error: string str = "woop"; Invoke(() => this.Text = str); // Error: Cannot convert lambda expression to type 'System.Delegate' // because it is not a delegate type Yet this works fine: string str = "woop"; Invoke((Action)(() => this.Text = str)); When the method expects a plain Delegate? 回答1: A lambda expression can either be converted to a delegate type or an expression tree - but it has