type-conversion interview questions
Top type-conversion frequently asked interview questions
How do you convert a Unicode string (containing extra characters like £ $, etc.) into a Python string?
Source: (StackOverflow)
In java, what is the best way to convert a double to a long?
Just cast? or
double d = 394.000;
long l = (new Double(d)).longValue();
System.out.println("double=" + d + ", long=" + l);
Source: (StackOverflow)
How can I convert a String to an int in Java?
My String contains only numbers and I want to return the number it represents.
For example, given the string "1234" the result should be the number 1234.
Source: (StackOverflow)
What is the best possible way to check if a string can be represented as a number in Python?
The function I currently have right now is:
def is_number(s):
try:
float(s)
return True
except ValueError:
return False
Which, not only is ugly and slow, seems clunky. However I haven't found a better method because calling float in the main function is even worse.
Source: (StackOverflow)
What is the easiest way to convert from int to equivalent string in C++. I am aware of two methods. Is there any easier way?
1.
int a = 10;
char *intStr = itoa(a);
string str = string(intStr);
2.
int a = 10;
stringstream ss;
ss << a;
string str = ss.str();
Source: (StackOverflow)
I want to use a track-bar to change a form's opacity.
This is my code:
decimal trans = trackBar1.Value / 5000;
this.Opacity = trans;
When I try to build it, I get this error:
Cannot implicitly convert type 'decimal' to 'double'.
I tried making trans a double, but then the control doesn't work. This code has worked fine for me in VB.NET in the past.
Source: (StackOverflow)
In development blogs, online code examples and (recently) even a book, I keep stumbling about code like this:
var y = x as T;
y.SomeMethod();
or, even worse:
(x as T).SomeMethod();
That doesn't make sense to me. If you are sure that x is of type T, you should use a direct cast: (T)x. If you are not sure, you can use as but need to check for null before performing some operation. All that the above code does is to turn a (useful) InvalidCastException into a (useless) NullReferenceException.
Am I the only one who thinks that this a blatant abuse of the as keyword? Or did I miss something obvious and the above pattern actually makes sense?
Source: (StackOverflow)
I'd like to set a property of an object through Reflection, with a value of type string.
So, for instance, suppose I have a Ship class, with a property of Latitude, which is a double.
Here's what I'd like to do:
Ship ship = new Ship();
string value = "5.5";
PropertyInfo propertyInfo = ship.GetType().GetProperty("Latitude");
propertyInfo.SetValue(ship, value, null);
As is, this throws an ArgumentException:
Object of type 'System.String' cannot be converted to type 'System.Double'.
How can I convert value to the proper type, based on propertyInfo?
Source: (StackOverflow)
I am absolutely new to Java and Blackberry development. I've started learning Java and Blackberry development. I just created sample BB app, which can allow to choose the date.
DateField curDateFld = new DateField("Choose Date: ",
System.currentTimeMillis(), DateField.DATE | DateField.FIELD_LEFT);
After choosing the date, i need to convert that long value to String, so that i can easily store the date value somewhere in database.
long date = curDateFld.getDate();
As i haven't found any link, could someone give me the link or idea how should i convert this long value to String? Also i want to convert then again back to long from String, i think for that i can use "long l = Long.parseLong("myStr");" ?
Source: (StackOverflow)
I want to get, given a character, its ASCII value.
For example, for the character a, I want to get 97, and vice versa.
Source: (StackOverflow)
With ARC, I can no longer cast CGColorRef to id. I learned that I need to do a bridged cast. According clang docs:
A bridged cast is a C-style cast annotated with one of three keywords:
(__bridge T) op casts the operand to the destination type T. If T
is a retainable object pointer type, then op must have a
non-retainable pointer type. If T is a non-retainable pointer type,
then op must have a retainable object pointer type. Otherwise the cast
is ill-formed. There is no transfer of ownership, and ARC inserts no
retain operations.
(__bridge_retained T) op casts the operand, which must have
retainable object pointer type, to the destination type, which must be
a non-retainable pointer type. ARC retains the value, subject to the
usual optimizations on local values, and the recipient is responsible
for balancing that +1.
(__bridge_transfer T) op casts the operand, which must have
non-retainable pointer type, to the destination type, which must be a
retainable object pointer type. ARC will release the value at the end
of the enclosing full-expression, subject to the usual optimizations
on local values.
These casts are required in order to transfer objects in and out of
ARC control; see the rationale in the section on conversion of
retainable object pointers.
Using a __bridge_retained or __bridge_transfer cast purely to convince
ARC to emit an unbalanced retain or release, respectively, is poor
form.
In what kind of situations would I use each?
For example, CAGradientLayer has a colors property which accepts an array of CGColorRefs. My guess is that I should use __brige here, but exactly why I should (or should not) is unclear.
Source: (StackOverflow)
How can I convert a string to a date time object in javascript by specifying a format string?
I am looking for something like:
var dateTime = convertToDateTime("23.11.2009 12:34:56", "dd.MM.yyyy HH:mm:ss");
Source: (StackOverflow)
I want to convert these types of values, '3', '2.34', '0.234343', etc. to a number. In JavaScript we can use Number(), but is there any similar method available in PHP?
Input Output
'2' 2
'2.34' 2.34
'0.3454545' 0.3454545
Source: (StackOverflow)