Note 1 :-
Use StringBuilder if you are planning to change/concatenate a string a lot, as it's slightly more efficient.
This is because a string type is immutable within the CLR, this means that if you do this:
string test = String.Empty();
test = test + "Hello";
test = test + " World!";
You've actually created 3 strings, one for each time it's been changed
Whereas
StringBuilder test = new StringBuilder();
test.Append("Hello");
test.Append(" World!");
This has created just ONE StringBuilder
StringBuilder in the Java world is called StringBuffer. I think!
Hope this has cleared it up!
Note 2:-
String are Immutable (Not Modifiable). If you try to modify the string it actually creates
a new string and the old string will be then ready for garbage collection.
StringBuilder when instantiated, creates a new string with predefined capacity and upto that
capacity it can accodomate string without needing to create a new memory location for the
string....i mean it is modifiable and can also grow as and when needed.
When the string needs to be modified frequently, preferably use StringBuilder as its optimized
for such situations.
Note 3 :-
Both String and StringBuilder are classes used to handle the strings.
The most common operation with a string is concatenation. This activity has to be
performed very efficiently.
When we use the "String" object to concatenate two strings, the first string is
combined to the other string by creating a new copy in the memory as a string object,
and then the old string is deleted.
This process is a little long. Hence we say "Strings are immutable".
When we make use of the "StringBuilder" object, the Append method is used.
This means, an insertion is done on the existing string.
Operation on StringBuilder object is faster than String operations, as the copy
is done to the same location. Usage of StringBuilder is more efficient in case large
amounts of string manipulations have to be performed.
