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I'm making an application in C#, based on Delphi (converting code), but I found a command that I do not recognize (shl), and i want to know if there is any equivalent to C#.

Thanks in advance.

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3 Answers 3

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Shl is left shift. Use << C# operator for the same effect.

Example:

uint value = 15;              // 00001111
uint doubled = value << 1;    // Result = 00011110 = 30
uint shiftFour = value << 4;  // Result = 11110000 = 240
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    Fun fact: x << y is also equivalent to x * 2 to the power of y. Likewise, x >> y divides by 2 y times
    – Rei Miyasaka
    Commented Mar 18, 2011 at 5:55
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    Another fun fact, C/C#'s >> operator is an arithmetic shift, that is, it shifts in 0s from the left on unsigned types but shifts in 1s on signed types, thus it always divides by 2. Delphi's shr function is a logical shift and always shifts-in 0s. (That was a comparison of C#4 & Delphi 7 btw - I can't find a formal definition of Delphi's shr).
    – MikeJ-UK
    Commented Mar 18, 2011 at 9:25
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From Shl Keyword this is a bitwise shift left which from C# Bitwise Shift Operators would be <<

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Shl is the shift left operator, in C# you use <<.

var
  a : Word;
begin
  a := $2F;   // $2F = 47 decimal
  a := a Shl $24;
end;

is the same as:

short a = 0x2F;
a = a << 0x24;
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  • 5
    They're the same, but only by accident. The Delphi code will truncate the $24 value to the lower 4 bits because a is a 16-bit type. The C# code will promote a to type int, which is a 32-bit type, and then truncate 0x24 to the lower 5 bits. In this case, that happens to be equal to the lower 4 bits, but shift by an amount that uses the fifth bit and you should see a difference.
    – Rob Kennedy
    Commented Mar 18, 2011 at 7:10

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