attributes – Page 11

Inheritance of Custom Attributes on Abstract Properties

May 6, 2023 by Tarik

Instead of calling PropertyInfo.GetCustomAttributes(…), you have to call the static method System.Attribute.GetCustomAttributes(pi,…), as in: PropertyInfo info = GetType().GetProperties(); // this gets only the attributes in the derived class and ignores the ‘true’ parameter object[] DerivedAttributes = info.GetCustomAttributes(typeof(MyAttribute),true); // this gets all of the attributes up the heirarchy object[] InheritedAttributes = System.Attribute.GetCustomAttributes(info,typeof(MyAttribute),true);

How can a function access its own attributes?

May 5, 2023 by Tarik

Solution Make one of the function’s default arguments be a reference to the function itself. def f(self): return self.x f.func_defaults = (f,) Example usage: >>> f.x = 17 >>> b = f >>> del f >>> b() 17 Explanation The original poster wanted a solution that does not require a global name lookup. The simple … Read more

NewtonSoft add JSONIGNORE at runTime

May 5, 2023 by Tarik

No need to do the complicated stuff explained in the other answer. NewtonSoft JSON has a built-in feature for that: public bool ShouldSerializeINSERT_YOUR_PROPERTY_NAME_HERE() { if(someCondition){ return true; }else{ return false; } } It is called “conditional property serialization” and the documentation can be found here. Warning: first of all, it is important to get rid … Read more

attribute((const)) vs attribute((pure)) in GNU C

May 2, 2023 by Tarik

From the documentation for the ARM compiler (which is based on gcc): __attribute__((pure)) function attribute Many functions have no effects except to return a value, and their return value depends only on the parameters and global variables. Functions of this kind can be subject to data flow analysis and might be eliminated. __attribute__((const)) function attribute … Read more

How to remove read-only attrib directory with Python in Windows?

May 1, 2023 by Tarik

If you are using shutil.rmtree, you can use the onerror member of that function to provide a function that takes three params: function, path, and exception info. You can use this method to mark read only files as writable while you are deleting your tree. import os, shutil, stat def on_rm_error( func, path, exc_info): # … Read more

Add and remove attribute with jquery

May 1, 2023 by Tarik

It’s because you’ve removed the id which is how you’re finding the element. This line of code is trying to add id=”page_navigation1″ to an element with the id named page_navigation1, but it doesn’t exist (because you deleted the attribute): $(“#page_navigation1”).attr(“id”,”page_navigation1″); Demo: If you want to add and remove a class that makes your <div> red … Read more

Looping over a Date or POSIXct object results in a numeric iterator

April 28, 2023 by Tarik

Can C# Attributes access the Target Class?

April 25, 2023 by Tarik

There are cases where you can’t rely on the calling code to pass a type reference. Below is a solution I cooked up to solve this problem. It’s a bit of a shot-gun approach, but it does work… using System; using System.Reflection; using System.Collections.Generic; using System.Linq; using System.Diagnostics; namespace Ethica.Reflection { /// <summary> /// Helps … Read more

What are the similarities and differences between Java Annotations and C# Attributes?

April 25, 2023 by Tarik

Control over when your metadata is made accessible is different between the two languages. Java provides the java.lang.annotation.Retention annotation and java.lang.annotation.RetentionPolicy enum to control when annotation metadata is accessible. The choices vary from Runtime (most common – annotation metadata retained in class files), to Source (metadata discarded by compiler). You tag your custom annotation interface … Read more

What is XHTML role attribute? What do you use it for?

April 24, 2023 by Tarik

The Short Version: The Role Attribute may give future browsers a way to work intelligently with certain XML elements in a device-independent way. For example, an unordered list that is marked with the role attribute of “navigation” can be interpreted intelligently on browsers in both desktop and handheld environments, allowing it to be displayed clearly … Read more