why is string value not changed?

Valerie Meunier

string is reference type, so why do i get this with the code below: Joe Joe Bill, Joe?

I would expect Joe Joe Bill, Bill because string is not a value variable.

Thanks again

string str = "Joe";
string str2 = str;
Console.WriteLine(str);
Console.WriteLine(str2);

str = "Bill";
Console.WriteLine(str);
Console.WriteLine(str2);

4 Replies

Know the answer? Post it — somebody with the same question will find it here.

Rajeev Kumar3y ago
Accepted answer
String value can not be changed Because it is Refrence Type and a string is immutable each and every time it store a new addres for memory Location.
0
Satya Karki5y ago
Hi,

The output is correct as you are not changing the value.

This is because of Immutability of String Objects
Example:
string s1 = "abc";
string s2 = s1;
s1 = "def";
Console.WriteLine(s2);
// Output: abc
Check this
https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/strings/#immutability-of-string-objects
+1
Valerie Meunier5y ago
Thanks
0
Sachin Singh5y ago
Yes, this is the most famous interview question as well.
The answer is c# strings are immutable, each time a new value is assigned to the string a new memory location is created.
means if you will do
for(int i=0; i<1000;i++)
{
str= str+i;

}
then it means 1000 new memory locations will be created, to avoid this we use StringBuilder and append the value instead of simply concatenating.
If the value is not changed then no new memory location will be created.
for(int i=0; i<1000;i++)
{
str= str;

}
so, above there will be one memory location, this is called interning.
so, yes string are reference type but behave as value types.
0