what is type-safe in visual studio.net?

Question

hi, can i know what is type-safe please. thank you

Answer 1

Type-safe code accesses only the memory locations it is authorized to access. For example, type-safe code cannot read values from another object's private fields. It accesses types only in well-defined, allowable ways.

During just-in-time (JIT) compilation, an optional verification process examines the metadata and Microsoft intermediate language (MSIL) of a method to be JIT-compiled into native machine code to verify that they are type safe. This process is skipped if the code has permission to bypass verification

Although verification of type safety is not mandatory to run managed code, type safety plays a crucial role in assembly isolation and security enforcement. When code is type safe, the common language runtime can completely isolate assemblies from each other. This isolation helps ensure that assemblies cannot adversely affect each other and it increases application reliability.

For more refer msdn link

A good article explaining it is here

Answer 2

C - You declare an int, cast it to char and access memory beyond int's boundary

int i = 10;
char *s = (char*)i;
print(*(s+10));

C# - Types are safe

int i = 10;
char *s >> This is invalid unless you are using unsafe context. 

Pointers are not directly supported by .NET

Answer 3

If you're asking what the idea of "type-safe" in general means, it's the characteristic of code that allows the developer to be certain that a value or object will exhibit certain properties (i.e., be of a certain type) so that he/she can use it in a specific way without fear of unexpected or undefined behavior.

For instance, in C#, you could say the ArrayList class is not type-safe because it can store any object, which means you can do something like the following:

var integers = new ArrayList();
integers.Add(1);
integers.Add(2);
integers.Add("3");

for (int i = 0; i < integers.Count; ++i) {
    int integer = (int)integers[i];
    // do something
}

The above will compile because the value "3", even though it's a string and not an integer, can legally be added to an ArrayList since String derives (like Int32) from Object. However, it will throw an InvalidCastException when you try to set integer to (int)integers[2] because a String cannot be cast to an Int32.

On the other hand, the List<T> class is type-safe for exactly the opposite reason--i.e., the above code would not compile if integers were a List<int>. Any value that you the developer access from within a type-safe List<int> you can be certain is an int (or whatever the corresponding T is for any generic List<T>); and you can therefore be sure that you'll be able to perform operations such as casting to int (obviously) or, say, long.