C# validate textbox not null

Show "You have to enter an age" ; textBox1. ToInt32 textBox1. Still does not work :. Now, what error are you getting or what you are not able to achive? It tells me to enter something in the textbox1. What are your requirements? What do you want the code to do? And what is there in the textbox? I will tell you.. I did something and it works. This method is not recommended because it does not take whitespaces into consideration.

Length Property in C This tutorial will discuss how to check if a text box is empty or not in C. IsNullOrEmpty textBox1. IsNullOrWhitespace textBox1. DelftStack is a collective effort contributed by software geeks like you. Thanks Rahul. EdH Oct pm.

Posted Nov pm Krunal Rohit. Balamurugan Nov am. It shows the error i. I have updated the soultion, try that one.. I tried ur code only Tell me,Where are you writing this code?? And in my code, its working..

I would suggest using string. Empty instead of "" in the comparison though. For Empty textbox validation we need to follow the below code: C. Silvabolt Jul pm. This would only show one error at a time.

Rather than doing this, you can check all fields at once, save them and notify user all of the errors at once. Furthermore, string. Empty should be used instead of "". Also, all of the solutions including these ones will break if textbox happens to be null. Solution 3 makes a good remark about the 'return', because this is probably handled in an event handler method. I know this is old, but none of these solutions are really complete.

Show "This field cannot left empty! Active Oldest Votes. IsNullOrEmpty to make sure it is neither empty nor null somehow : if String. IsNullOrEmpty textBox1. Improve this answer. I think string. Text or string. Text are your best options. PiotrWolkowski PiotrWolkowski 7, 5 5 gold badges 39 39 silver badges 64 64 bronze badges.

IsNullOrWhitespace is probably better because it fits most people's idea of what "empty" means. I agree, it's not often that a couple of spaces is an expected input from a user. IsEmpty explanation Help Text WaterMark to Disappear when user Types in answer this is the full example which I used from the partial answer given above. Another way: if textBox1.

Show "The texbox is empty! D J D J 6 6 silver badges 25 25 bronze badges. IsNullOrWhiteSpace txt. Show "The TextBox is empty! Shams Tech Shams Tech 97 7 7 bronze badges. Farhan answer is the best and I would like to add that if you need to fullfil both conditions adding the OR operator works, like this: if string. IsNullOrEmpty text. Text string.