The basic arithmetic operators in PowerShell and the all important "Left Hand" rule!
Here are basic arithmetic operators in PowerShell:
The addition operator – Add two values together
Example: 2 + 4 = 6
“Hello” + “World” = “Hello World”
1,2,3 + 4,5,6 = 1,2,3,4,5,6
The multiplication operator – Multiply 2 values
Example: 2 * 4 = 8
“x” * 3 = “xxx”
1,2 * 2 = 1,2,1,2
The subtraction operator – Subtract one value from another
Example: 8 – 4 = 4
The division operator – Divide two values
Example: 8 / 4 = 2
9 / 6 = 1.5
The modulus operator – Return the remainder from a division operation
Example: 7 % 4 = 3
As you can see, when we adding or multiplying two numbers produces a numeric result. Adding two stings performs a string concatenation, resulting a new string, and adding two arrays joins the two arrays (array catenation), producing a new array. It’s get interesting when you mix operand types. In this situation, the type of left operand determines how the operation will proceed ( “Left-Hand” rule!). Let’s see the below example:
PS P:\> 5 + "125"
130
Left operand is number, PowerShell convert the right operand to a number
PS P:\> "5" + 125
5125
Left operand is string, the operand on the right (the number 125) is converted to a string and appended to “5” to produce a new sting “5125”
If the right operand can’t be converted into the type of the left operand then a type conversion error will be raised:
PS P:\> 5 + "xyz"
Cannot convert value "xyz" to type "System.Int32". Error: "Input string was not in a correct format."
At line:1 char:4
+ 5 + <<<< "xyz"
You got the idea…