Allow only decimal numbers in textbox in C#

by

Although NumericUpDown is a good choice, but you want a textbox after all, right?

Here is a general guide. First you need to subscribe to the TextChanged event of the textbox. This can be done by double clicking the textbox in the designer. When the event happens, you want to check the textbox’s text. If it is empty string, just return. Now you can try to convert the text to a double. If it can’t be converted, set the text to the original text.

You might want to have a originalText variable somewhere in the class. If it converts to a double successfully, set the original text to the text.

try {
    Convert.ToDouble(textbox1.Text);
} catch (NumberFormatException) {
    textbox1.Text = originalText;
    return;
}
originalText = textbox1.Text;

Now it should work!

More Related Contents:

  1. How do I display a decimal value to 2 decimal places?
  2. Remove trailing zeros
  3. Decimal precision and scale in EF Code First
  4. How To Represent 0.1 In Floating Point Arithmetic And Decimal
  5. decimal vs double! – Which one should I use and when? [duplicate]
  6. Formatting a float to 2 decimal places
  7. Why can’t I unbox an int as a decimal?
  8. Regular expression for decimal number
  9. Format Number like Stack Overflow (rounded to thousands with K suffix)
  10. Best way to display decimal without trailing zeroes
  11. Generics – where T is a number? [duplicate]
  12. How to get the closest number from a List with LINQ?
  13. How to extract the decimal part from a floating point number in C?
  14. C# Random Numbers aren’t being “random”
  15. How can I get a count of the total number of digits in a number?
  16. Generating a Random Decimal in C#
  17. Convert string to decimal, keeping fractions
  18. Standalone numbers Regex?
  19. String to decimal conversion: dot separation instead of comma
  20. Conversion of a decimal to double number in C# results in a difference
  21. Rounding down to 2 decimal places in c#
  22. Performing Math operations on decimal datatype in C#?
  23. Read numbers from the console given in a single line, separated by a space
  24. Why c# decimals can’t be initialized without the M suffix?
  25. Octal equivalent in C#
  26. Why am I getting a compile error when multiplying a decimal by a literal value?
  27. How can I format decimal property to currency?
  28. C# Check if a decimal has more than 3 decimal places?
  29. Formatting Numbers as Strings with Commas in place of Decimals
  30. Raising a decimal to a power of decimal?

Leave a Comment