Switch v If statement

[Alvin Bruney]

Is a switch more efficient than an if statement? I observe thru the debugger
that a switch statement jumps directly to its case handler where as an if
statement examines all conditions sequentially. Is that a trick of the
debugger or is a switch quicker by O(n).

 

[Jip from Paris]

Is a switch more efficient than an if statement? I observe thru the debugger
that a switch statement jumps directly to its case handler where as an if
statement examines all conditions sequentially. Is that a trick of the
debugger or is a switch quicker by O(n).

No trick. The switch statement is basically a direct jump to one of many
targets using the content of an internal table and an index computed from
the switch expression. An if ... elseif ... elseif ... statement chain is
slower. However such a chain allows for complex composite conditions that
would be very difficult or impossible to handle using a switch statement.

 

[Hilton]

I really wish C# allowed variables in the case; i.e. "case firstName". It
can optimize 'constant' case statements, but variables would be very nice.

Hilton

 

[Umpa Lumpa]

also confusing as hell.

I really wish C# allowed variables in the case; i.e. "case firstName". It
can optimize 'constant' case statements, but variables would be very nice.

Hilton

 

[Paul E Collins]

also confusing as hell.

Reminds me of how some menu systems used to work in BASIC.

GOTO 1000 + 100 * option

P.

 

[Hilton]

You think a bunch of "if" statements make things clearer? Different views I
guess. I just view the "case" as a neat way of bundling up "if"
statements...

Hilton