Question

I am getting data into a text field and I need to display it as a percentage. Is there a function to perform this?

Ex: in my column I have "0.5", "0.1","0.2","0.25" etc., which needs to be displayed as
50%,10%,20%,25% etc., What is the best way to do it?

Answer 1

You should do this in two phases:

• Parse the text as a number so you’ve got the value as your “real” type. (As a general rule, parse from text as early as you can, and format to a string as late as you can… operations between the two will be a lot simpler using the natural type.)
• Format the number as a percentage using the standard numeric format string for percentage

So:

decimal percentage = decimal.Parse(input);
string output = percentage.ToString("p0");

Notes:

• You should consider both input and output culture; are you always expecting to use “.” as the decimal separator, for example?
• Use decimal rather than double to exactly represent the value in the text (for example, the text could have “0.1” but double can’t hold a value of exactly 0.1)
• You can add things like desired precision to the formatting; see the linked docs for details; the example gives just an integer percentage, for example