I have four questions:

 1. Does C# have `int8`
 2. If so, how can I convert a `string` to `int8`?
 3. Does C# have `uint8`
 4. If that how can I convert a `string` to `uint8`?



Does C# have int8 and uint8?

In the code review process, one of my coworkers mentioned to me that &quot;const&quot;s in front of &quot;primitive types&quot; used as a function parameter in a header is meaningless, and he recommended to remove these &quot;const&quot;s. He suggested using &quot;const&quot; only in the source file in such cases. Primitive types mean types such as &quot;int&quot;, &quot;char&quot;, &quot;float&quot;, etc.

The following is example.

example.h

    int ProcessScore(const int score);

example.cc

    int ProcessScore(const int score) {
      // Do some calculation using score
      return some_value;
    }

His suggestion is doing as follows:

example.h

    int ProcessScore(int score);  // const is removed here.

example.cc

    int ProcessScore(const int score) {
      // Do some calculation using score
      return some_value;
    }

But I&#39;m somewhat confused. Usually, the user will look at only the header, so if there is inconsistency between the header and the source file, it might cause confusion.

Could anyone give some advice on this?

Is it better to remove &quot;const&quot; in front of &quot;primitive&quot; types used as function parameters in the header?

Here is the question: write a method that swaps two variables. These two variables should be primitives. It doesn&#39;t need to be generic e.g. two `int` variables. Is there a way?!

Is it possible to write swap method in Java?

When declaring any primitive type data like `int` or `double` they get initialized to `0` or `0.0`. Why can we not set them to `null`?

Why can&#39;t primitive data types be &quot;null&quot; in Java?

How do `System.float`, `System.int` and other primitives types work? I never understood how it was possible to make primitives structs and I wonder if I could make my own numeric type. &amp;nbsp;


How are primitive data types made in C#?

How can I pass a primitive type by reference in java? For instance, how do I make an `int` passed to a method modifiable?

How do I pass a primitive data type by reference?

Is there a &quot;typeof&quot; like function in Java that returns the type of a primitive data type (PDT) variable or an expression of operands PDTs?

`instanceof` seems to work for class types only.




How to determine the primitive type of a primitive variable?

I have a block of code that serializes a type into a Html tag.

    

    Type t = typeof(T); // I pass &lt;T&gt; in as a paramter, where myObj is of type T
    tagBuilder.Attributes.Add(&quot;class&quot;, t.Name);
    foreach (PropertyInfo prop in t.GetProperties())
    {
        object propValue = prop.GetValue(myObj, null);
        string stringValue = propValue != null ? propValue.ToString() : String.Empty;
        tagBuilder.Attributes.Add(prop.Name, stringValue);
    }

This works great, except I want it to only do this for primitive types, like `int`, `double`, `bool` etc, and other types that aren&#39;t primitive but can be serialized easily like `string`. I want it to ignore everything else like Lists &amp; other custom types.

Can anyone suggest how I do this? Or do I need to specify the types I want to allow somewhere and switch on the property&#39;s type to see if it&#39;s allowed? That&#39;s a little messy, so it&#39;d be nice if I there was a tidier way.

How To Test if Type is Primitive

Since Java 5, we&#39;ve had boxing/unboxing of primitive types so that `int` is wrapped to be `java.lang.Integer`, and so and and so forth. 

I see a lot of new Java projects lately (that _definitely_ require a JRE of at least version 5, if not 6) that are using `int` rather than `java.lang.Integer`, though it&#39;s much more convenient to use the latter, as it has a few helper methods for converting to `long` values et al. 

Why do some __still__ use primitive types in Java? Is there any tangible benefit?

Why do people still use primitive types in Java?

In various articles I have read, there are sometimes references to primitive data types and sometimes there are references to scalars.

My understanding of each is that they are data types of something simple like an int, boolean, char, etc.

Is there something I am missing that means you should use particular terminology or are the terms simply interchangeable?
The Wikipedia pages for each one doesn&#39;t show anything obvious.

If the terms are simply interchangeable, which is the preferred one?

Scalar vs. primitive data type - are they the same thing?

I am writing a little code in J2ME. I have a class with a method `setTableId(Short tableId)`. Now when I try to write `setTableId(100)` it gives compile time error. How can I set the short value without declaring another short variable?

When setting `Long` value I can use `setLongValue(100L)` and it works. So, what does `L` mean here and what&#39;s the character for `Short` value? 

Thanks

Setting Short Value Java

Java collections only store Objects, not primitive types; however we can store the wrapper classes.

Why this constraint?


Why can Java Collections not directly store Primitives types?

How can I convert a `NSString` containing a number of any primitive data type (e.g. `int`, `float`, `char`, `unsigned int`, etc.)? The problem is, I don&#39;t know which number type the string will contain at runtime.

I have an idea how to do it, but I&#39;m not sure if this works with any type, also unsigned and floating point values:

    long long scannedNumber;
    NSScanner *scanner = [NSScanner scannerWithString:aString];
    [scanner scanLongLong:&amp;scannedNumber]; 
    NSNumber *number = [NSNumber numberWithLongLong: scannedNumber];

Thanks for the help.

How to convert an NSString into an NSNumber

How do I hard code an absolute maximum or minimum value for a float or double? I want to search out the max/min of an array by simply iterating through and catching the largest.

There are also positive and negative infinity for floats, should I use those instead? If so, how do I denote that in my code?

how do I initialize a float to its max/min value?

When I should go for wrapper class over primitive types? Or On what circumstance I should choose between wrapper / Primitive types?

When to use wrapper class and primitive type

I&#39;ve noticed I&#39;ve always used int and doubles no matter how small or big the number needs to be. So in java, is it more efficient to use `byte` or `short` instead of `int` and `float` instead of `double`?

So assume I have a program with plenty of ints and doubles. Would it be worth going through and changing my ints to bytes or shorts if I knew the number would fit?

I know java doesn&#39;t have unsigned types but is there anything extra I could do if I knew the number would be positive only?

By efficient I mostly mean processing. I&#39;d assume the garbage collector would be a lot faster if all the variables would be half size and that calculations would probably be somewhat faster too.
( I guess since I am working on android I need to somewhat worry about ram too)

(I&#39;d assume the garbage collector only deals with Objects and not primitive but still deletes all the primitives in abandoned objects right? )

I tried it with a small android app I have but didn&#39;t really notice a difference at all. (Though I didn&#39;t &quot;scientifically&quot; measure anything.) 

Am I wrong in assuming it should be faster and more efficient? I&#39;d hate to go through and change everything in a massive program to find out I wasted my time.

Would it be worth doing from the beginning when I start a new project? (I mean I think every little bit would help but then again if so, why doesn&#39;t it seem like anyone does it.)

In java, is it more efficient to use byte or short instead of int and float instead of double?

I have an array declaration like this:

    int a[];

Here `a` is an array of primitive `int` type. Where is this array stored? Is it stored on heap or stack? This is a primitve type `int`, all primitive types are not stored on heap.

Is a Java array of primitives stored in stack or heap?

If you have an array of Java objects which have a primitive type (for example Byte, Integer, Char, etc).  Is there a neat way I can convert it into an array of the primitive type?  In particular can this be done without having to create a new array and loop through the contents.

So for example, given

    Integer[] array
what is the neatest way to convert this into

    int[] intArray

Unfortunately, this is something we have to do quite frequently when interfacing between Hibernate and some third party libraries over which we have no control.  It seems this would be a quite common operation so I would be surprised if there&#39;s no shortcut.

Thanks for your help!




Converting an array of objects to an array of their primitive types

I am curious about the string and primitive types. Article like [this][1] says string is primitive type. However [second article][2] on MSDN does not list string as primitive type. 

However when I ran the code provided in second article, it displays **String is not Primitive type**.

Can any one guide me on this?

  [1]: http://msdn.microsoft.com/en-us/library/aa711900%28VS.71%29.aspx
  [2]: http://msdn.microsoft.com/en-us/library/system.type.isprimitiveimpl%28v=VS.100%29.aspx

Is String a primitive type?

I&#39;d like to know whether one can type-hint a method to expect primitive types?

Something like this:

    public function someMethod(string $str)
                             //^^^^^^

Or:

    private function anotherMethod(int $num)
                                 //^^^


the same way you would:

    private function otherMethod(Person $rambo)
                               //^^^^^^


Is that possible in php?

PHP type-hinting to primitive values?

I&#39;m trying to convert an ArrayList containing Integer objects to primitive int[] with the following piece of code, but it is throwing compile time error. Is it possible to convert in Java?

    List&lt;Integer&gt; x =  new ArrayList&lt;Integer&gt;();
    int[] n = (int[])x.toArray(int[x.size()]);



How to convert an ArrayList containing Integers to primitive int array?

Why must local variables, including primitives, always be initialized in Java?  Why is the same not applicable in the case of instance variables?

Why must local variables, including primitives, always be initialized in Java?

Let&#39;s say I have a **LazySeq** of *java.lang.Character* like

    (\b \ \! \/ \b \ \% \1 \9 \/ \. \i \% \$ \i \space \^@)

How can I convert this to a String? I&#39;ve tried the obvious

    (String. my-char-seq)

but it throws

    java.lang.IllegalArgumentException: No matching ctor found for class java.lang.String (NO_SOURCE_FILE:0)
    [Thrown class clojure.lang.Compiler$CompilerException]

I think because the String constructor expects a primitive **char[]** instead of a **LazySeq**. So then I tried something like

    (String. (into-array my-char-seq))

but it throws the same exception. The problem now is that **into-array** is returning a **java.lang.Character[]** instead of a primitive **char[]**. This is frustrating, because I actually generate my character sequence like this

    (map #(char (Integer. %)) seq-of-ascii-ints)

Basically I have a seq of ints representing ASCII characters; 65 = A, etc. You can see I explicitly use the primitive type coercion function **(char x)**.

What this means is that my **map** function is returning a primitive **char** but the Clojure **map** function overall is returning the *java.lang.Character* object.
 






How can I convert a LazySeq of Characters to a String in Clojure?

What&#39;s the difference between NSNumber and NSInteger? Are there more primitives like these that I should know about? Is there one for floats?

All Primitive Types Solutions on Gang of Coders

Total of 24 Primitive Types Solutions