Converting Base Numbers with PowerShell

One of the points that I try to get across the IT Pros taking my PowerShell classes is that if it works, then it is correct. That does not take efficacy into consideration. However, when you are scripting (or writing software) you need to accept that there are multiple paths to success. We are going to take a look at the Convert class of .Net to make some numeric conversions.

There are 3 numeric bases that are common in the computer science world. Decimal because we as humans like it. Binary, because that is how a computer works. Hexadecimal because it allows us to represent 4 bits with a single character. Yes there are other reasons but let’s just keep this simple.

The last time I checked, the convert class provide over 290 overloaded static methods to help you perform conversions. Below I provided the code to convert between our big 3.

#region Convert to Base 16 ----------------------------------------------------

# From Base 2

[Convert]::ToString(11001100,16)

# From Base 10

[Convert]::ToString(154,16)

"{0:X4}" -f 154

#endregion Convert to Base 16 -------------------------------------------------

#region Convert to Base 10 ----------------------------------------------------

# From Base 2

[Convert]::ToInt32(10110010,2)

# From Base 16

[Convert]::ToInt32("FA",16)

#endregion Convert to Base 10 -------------------------------------------------

#region Convert to Base 2 ----------------------------------------------------

# From Base 10

[Convert]::ToString(100,2)

# From Base 16

[Convert]::ToString([Convert]::ToInt32("FA",16),2)

#endregion Convert to Base 2 -------------------------------------------------

Obviously their can be other ways to achieve some of these conversions. Take a look at the last one. We actually had to perform 2 conversions. One to Base 10 and then to Base 2. In any case, I often get asked about these conversions from my more advanced students so here they are!

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