default list for various data types
vb2005
when i declare a data type (e.g. Dim total as Double), what is the default value which variable total gets instanced with?
i would like a list or a link that tells which are the defaulted values for each data type. my goal is to not be redundant if i declare like Dim total as Double = 0, because maybe 0 is the default instanced value for that variable.
thanks
when i declare a data type (e.g. Dim total as Double), what is the default value which variable total gets instanced with?
i would like a list or a link that tells which are the defaulted values for each data type. my goal is to not be redundant if i declare like Dim total as Double = 0, because maybe 0 is the default instanced value for that variable.
thanks
SOLUTION
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Default string value is Nothing, since this is reference type.
Default value of numeric type is 0, Boolean is false.
Test your program with Microsoft FxCop program, it shows all unnecessary initializations (among lot of other very useful things).
Default value of numeric type is 0, Boolean is false.
Test your program with Microsoft FxCop program, it shows all unnecessary initializations (among lot of other very useful things).
actually, in .net, variables all default to null object, hence are not initalialzed (my comment above was in the context of vb6, sorry)
you need to initalize all your variables, of any data type.
you need to initalize all your variables, of any data type.
ASKER
angel, so you mean i need to put a value to every declaration?
alex thanks for some clarifications.
finally, this question would obviusly go in the following direction:
is there a performace improvement if i declare and initialize every variable to its default value? i mean, does
Dim total as Double , and
Dim total as Double = 0
have any performance gains or any other benefit besides good coding practices?
thanks to both for your answers
alex thanks for some clarifications.
finally, this question would obviusly go in the following direction:
is there a performace improvement if i declare and initialize every variable to its default value? i mean, does
Dim total as Double , and
Dim total as Double = 0
have any performance gains or any other benefit besides good coding practices?
thanks to both for your answers
Not exactly, Microsoft coding guidelines recommend to avoid unnecessary initialization of value types, if initial value is equal to default. All default null is right for reference types.
FxCop handles this situation:
http://www.gotdotnet.com/team/fxcop/
FxCop handles this situation:
http://www.gotdotnet.com/team/fxcop/
ASKER CERTIFIED SOLUTION
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ASKER
great, thanks to both of you for the answers. i will increase points to split between both. thanks again
ASKER