Convert varbinary to base64 in .NET

Question

In this question I asked how can I convert varbinary to valid BASE64 string value in MSSQL.

Now I'd like to know how can it be done without MSSQL (in .NET f.e.).

Let's think of a method which accepts the following string (or byte array)

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

and returns valid BASE64

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

Well which are you interested in - converting a hex string, or converting a byte array? Those are two different questions with different answers. (I suspect both have been asked before.) `Convert.ToBase64String` is what you're after, basically. It's not clear why you've tagged this sql-server and varbinary if you need to do it *without* SQL. — Jon Skeet, Aug 15 '17 at 13:04
Duplicates: https://stackoverflow.com/questions/11809675 for byte array to base64; https://stackoverflow.com/questions/41963481 for hex to byte array — Jon Skeet, Aug 15 '17 at 13:13
I was not sure what MSSQL returns me. LinqPad5 returns me already converted string. That's why I included MSSQL tag. It was for completeness of the question. Thanks for the links! — pizycki, Aug 15 '17 at 13:18
"I was not sure what MSSQL returns me." It sounds like you should be able to have checked that before asking the question though, at which point the SQL would have been irrelevant. "LinaPad5 returns me already converted string." What is LinaPad5 and what does it have to do with the question? If you mean LINQPad, you should be able to do research *not* in LINQPad, unless your final code really needs to be running in LINQPad. — Jon Skeet, Aug 15 '17 at 13:19

score 3 · Accepted Answer · answered Aug 15 '17 at 13:04

3

Look at the Convert.ToBase64String() method.

answered Aug 15 '17 at 13:04

Joel Coehoorn

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That is correct. `ToBase64String` works. I was trying with casting to `byte[]` and then encoding with different (`UTF8`, `UTF16`, `ASCII`), but completely forgot about this one. This answer will be accepted. – pizycki Aug 15 '17 at 13:13

score 0 · Answer 2 · answered Aug 15 '17 at 13:08

0

You can use C# method Convert.ToBase64String() for this. Pass the byte array to this method as parameter and it will return it's base64 string.

answered Aug 15 '17 at 13:08

Akshey Bhat

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Convert varbinary to base64 in .NET

2 Answers2