how to validate if the text in edit has numbers in and to show a message if it has in delphi
To validate if the text in an edit control has numbers in it and show a message if it does in Delphi, you can use the StrToIntDef
function to attempt to convert the text to an integer. If the conversion is successful, it means that the text contains numbers. Here's an example of how you can achieve this:
var
inputText: string;
inputValue: Integer;
begin
inputText := Edit1.Text;
try
inputValue := StrToIntDef(inputText, 0);
if inputValue <> 0 then
ShowMessage('The text contains numbers.')
else
ShowMessage('The text does not contain numbers.');
except
ShowMessage('Invalid input.');
end;
end;
In this example, we first retrieve the text from the edit control (Edit1.Text
) and store it in the inputText
variable. We then use StrToIntDef
to attempt to convert the inputText
to an integer. If the conversion is successful and the resulting value is not equal to 0, we display a message indicating that the text contains numbers. If the conversion fails or the resulting value is 0, we display a message indicating that the text does not contain numbers. If an exception is raised during the conversion process, we handle it by displaying an "Invalid input" message.