Convert.ToString

Davin Martyn

12y1.4kVisual Basic .NET

Hi...

Difference between convert.tostring and .tostring in c# with example?

4 Replies

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Vulpes12y ago
Accepted answer
Well, Convert.ToString("25") will simply return the string "25" because the argument is already a string and so no further conversion is necessary.

As far as ToString("25") is concerned, it depends on what type of instance it's applied to, whether that's type's ToString method has been overloaded to take a string parameter and (if it has) whether "25" is a meaningful value for that parameter.

In the case of the basic numeric types (int, long, double etc), it again returns the string "25" regardless of the value to which it's applied:

int j = 20;
s = j.ToString("25");
Console.WriteLine(s); // 25

In the case of the string or object types, you'll get a compiler error because there is no overload of ToString which takes a string parameter.
Davin Martyn12y ago
What is the output of following statement ? convert.tostring("25") and .tostring("25")
Vulpes12y ago
Convert.ToString also has some overloads for converting the basic integral types (byte, short, int, long etc.) to different bases (binary, octal or hex) which aren't available with the ToString methods of those types.

For example:

int i = 32;
string bin = Convert.ToString(i, 2); // 100000
string oct = Convert.ToString(i, 8); // 40
string hex = Convert.ToString(i, 16); // 20
Ramesh Maruthi12y ago
Convert.ToString() handles null, while ToString() doesn't.

//Returns a null reference exception for str.
string str;
object i = null;
str = i.ToString();

//Returns an empty string for str and does not throw an exception. If you dont
string str;
object i = null;
str = Convert.ToString(i);