For example, I have two string variables:
string a = " Hello ";
string b = " World ";
How can I swap it without a temporary variable?
I found an example, but it used a third variable for the length of a:
int len1 = a.Length;
a = a + b;
b = a.Substring(0, len1);
a = a.Substring(len1);
How can I do that?
UPD, suggested solution for decimal data type, in ma case i've asked about string data type.
You can use SubString without using a temp variable, like this:
string a = " Hello ";
string b = " World ";
a = a + b;//" Hello World "
b = a.Substring(0, (a.Length - b.Length));//" Hello "
a = a.Substring(b.Length);//" World "
Just use some other means of swapping.
string stringOne = "one";
string stringTwo = "two";
stringOne = stringOne + stringTwo;
stringTwo = stringOne.Substring(0, (stringOne.Length - stringTwo.Length));
stringOne = stringOne.Substring(stringTwo.Length);
// Prints stringOne: two stringTwo: one
Console.WriteLine("stringOne: {0} stringTwo: {1}", stringOne, stringTwo);
string str1 = "First";
string str2 = "Second";
str1 = (str2 = str1 + str2).Substring(str1.Length);
str2 = str2.Substring(0,str1.Length-1);
I'm fond of doing it this way although underneath it's using resources to make it fully thread-safe, and I wouldn't be surprised if it was using a local variable behind the scenes.
string str1 = "First";
string str2 = "Second";
str2 = System.Interlocked.Exchange(ref str1, str2);
Interlocked.Exchangefor that: msdn.microsoft.com/de-de/library/f2090ex9(v=vs.110).aspx