We have been discussing data types over the past few postings. We have covered them from a very introductory, high level. I will have other posts where I will delve deeper, but today, I want to talk about how to declare a data type.
Now, before I dive in, I want you to understand something. I have been using JavaScript in my examples. I love JS. I use it a ton and I think it is an essential language that every developer should learn. With that being said, it is not a perfect language (which one is?). I have mentioned this before, but JavaScript is loosely typed. What that means is that when you create a variable, you do not have to state what data type it will contain. That is not true for strictly typed languages, such as C#, Java, etc. In those languages, you have to declare the data type.
So in JavaScript, you can create a variable along with changing data types as follow…
[code lang=”js”]
// Declare variable
var myVar;
// Instantiate variable with numeric data
myVar = 10;
// Change data value and therefore the type
myVar = "This is a string";
[/code]
So, as you can see, data type conversion is loose in JS. In other languages, you have to use the ‘new’ keyword to create a variable. In JS, this is only true of an Array, and even that has exceptions. You can use the new keyword in JS, but in some code quality tools (JSHint, etc.) this will throw an error. There is some scuttlebut about making the next version of JS strictly typed, but who knows when that will be done.
[code lang=”js”]
// Create a data type array
var myVar = new Array();
[/code]
Here is a C# example…
[code lang=”js”]
// An example of an integer
public int myNumber;
// An example of a string
public string myString;
[/code]
Happy Coding!
