Is there any CInt function - VB in c++?
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Dear c++ friends, In VB we have, Dim MyDouble, MyInt MyDouble = 2345.5678 ' MyDouble is a Double. MyInt = CInt(MyDouble) ' MyInt contains 2346. Is there anything in c++ similar to CInt in VB? Thanks, Joy Anne
Basic maths will do the trick. Try this:
double d = 2345.5678; int i = d + 0.5Steve -
hi, use reinterpret_cast value; snippet of code. int x; double y = 5.66; now x = reinterpret_cast y; // cast double to int data type. this is type conversion in c++. good luck, uday. uday kiran -- modified at 0:57 Wednesday 10th May, 2006
You don't need to use
reinterpret_castin this case and in fact shouldn’t: casting fromdoubletointis implicit so the following will do the trick:double d = 3.5; int i = d; // Ok, d=3Is you wanted to make the cast explicit (and there is good reason to do so as it will suppress a warning)static_castis the right cast for the job. i.e.double d = 3.5; int i = static_cast<int>(d);Part of the point of adding the function style casts was to make your intent specific thus it is important to use the right cast for the job. Steve -
Joy Anne wrote:
Dim MyDouble, MyInt MyDouble = 2345.5678 ' MyDouble is a Double. MyInt = CInt(MyDouble) ' MyInt contains 2346.
double myD = 2345.5678; int myI = (int)myD;
Maxwell Chen
This will not round. You need something like this:
double myD = 2345.5678; int myI = static_cast<int>(myD+0.5);Also note that I didn't use any C-style casts; they should never be used in C++ code. Steve -
This will not round. You need something like this:
double myD = 2345.5678; int myI = static_cast<int>(myD+0.5);Also note that I didn't use any C-style casts; they should never be used in C++ code. SteveWhich part did my 1-voter not like: The add 0.5 bit or the
static_castlecture? I stand by both of them but I believe that if you're going to down vote something in the programming forums it's good to reply and explain your objection. Steve -
Which part did my 1-voter not like: The add 0.5 bit or the
static_castlecture? I stand by both of them but I believe that if you're going to down vote something in the programming forums it's good to reply and explain your objection. SteveI voted 5 to balance it... :-D It used to happen on myself also, when someone doesn't feel like to see the truth. :doh: That's also the reason I posted some reply titled "WTF ?!", remember?! :-D
Maxwell Chen
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This will not round. You need something like this:
double myD = 2345.5678; int myI = static_cast<int>(myD+0.5);Also note that I didn't use any C-style casts; they should never be used in C++ code. SteveStephen Hewitt wrote:
any C-style casts; they should never be used in C++ code.
Personally I guess that the 1-voter doesn't feel comfortable with the sentence above.
Maxwell Chen
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Joy Anne wrote:
Dim MyDouble, MyInt MyDouble = 2345.5678 ' MyDouble is a Double. MyInt = CInt(MyDouble) ' MyInt contains 2346.
double myD = 2345.5678; int myI = (int)myD;
Maxwell Chen
So what's happening?! You guys like to vote 1 very much??
Maxwell Chen
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Stephen Hewitt wrote:
any C-style casts; they should never be used in C++ code.
Personally I guess that the 1-voter doesn't feel comfortable with the sentence above.
Maxwell Chen
I would guess so - nevertheless they shouldn't be used. Here are some reasons: - A wrong "bad" can cause havoc yet, if C-style casts are used you can’t “grep” the source code for them. - There are many distinct reasons to cast. For example, one is to remove const-ness; another is to “down-cast” in a class hierarchy. With C-style casts all casts look the same and so you have to guess at the intent. Function style casts are explicit and self documenting in this respect. - With C-style casts a simple mistake can change the type of cast and result in unintentional behaviour. For example if your casting to remove const-ness and then you change the type you’re casting it can changes into a “reinterpret” cast. With function style casts the compiler makes sure you can’t cast “more” then you should. i.e. a
const_castcan only remove const-ness and not change the type. - Casting is ugly – a well designed program shouldn’t have any – or at most only a few in the lowest level of a system. Casts should be ugly as design errors should be visible. I could go on. There are just so many problems it just not funny. Steve -
I would guess so - nevertheless they shouldn't be used. Here are some reasons: - A wrong "bad" can cause havoc yet, if C-style casts are used you can’t “grep” the source code for them. - There are many distinct reasons to cast. For example, one is to remove const-ness; another is to “down-cast” in a class hierarchy. With C-style casts all casts look the same and so you have to guess at the intent. Function style casts are explicit and self documenting in this respect. - With C-style casts a simple mistake can change the type of cast and result in unintentional behaviour. For example if your casting to remove const-ness and then you change the type you’re casting it can changes into a “reinterpret” cast. With function style casts the compiler makes sure you can’t cast “more” then you should. i.e. a
const_castcan only remove const-ness and not change the type. - Casting is ugly – a well designed program shouldn’t have any – or at most only a few in the lowest level of a system. Casts should be ugly as design errors should be visible. I could go on. There are just so many problems it just not funny. SteveStephen Hewitt wrote:
I could go on. There are just so many problems it just not funny.
What did you mean by that?
Maxwell Chen
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Stephen Hewitt wrote:
I could go on. There are just so many problems it just not funny.
What did you mean by that?
Maxwell Chen
Only that I could have made the list of problems with C-style casts longer. Steve