delphi edit control input

Hehe, the idea of the 2nd floor is like this:

varisid:boolean;

n:integer;

beginisid:=false;

for n:=1 to length( dobeginif in ['0'..'9'] thenbeginisid:=true;

endelse

beginisid:=false;

break;

end;end;

if isid then

begin is the student number.

endelse

begin is the name entered.

end;end;

for i:=0 to length( doif in [0..9] Then the input string is checked in a loop to determine if it is a number.

begin code query.

endelse

begin code query.

end；

You can get it with two edits, so why bother.

In the keypress thing Liang pickpocketing state Zheng Zhong processed.

This is a case that can only be handled for numbers.

if key<>#8 then

beginif(key<'0') or (key >'9') then

beginkey :=#

showmessage('Only numbers can be entered');

end;end;

This is a case that can only be handled for letters.

if key<>#8 then

beginif not(((key<='Sail key ode z') and (key>='a'))or ((key<='z') and (key>='a'))then

beginkey :=#

showmessage('Only letters can be entered');

end;end;

The built-in edit widget doesn't seem to have this functionality.

For example, tlabel has an alignment attribute to control.

If you want tedit to have this feature, either you write it yourself.

Either with 3-party controls.

For example, the faction edit in raize has an alignment property.

If you want to go down to the base of the wheel, you are fighting the letter.

Just search for raize.

The number to be displayed is: data

(formatfloat('',data));Or.

floattostr(round(data*100)/100);

The above two are rounded, but there is one thing that the syndicate should be aware of:

Take round as an example: round(The result is 4, but the result of round( is not 5 but 4, that is, 5 meets odd rounding, and the front meets even numbers; The same goes for formatfloat;

The above two are rounded, and there is a silver rock directly intercepted:

floattostr(trunc(data*100)/100);

This method is directly discarded no matter how many it is.

:=floattostr(int(strtofloat( /100);

As long as this is the repentance, the wide exchange is OK.,100 is a two-digit decimal place, if you want to increase the decimal place, you can directly modify this value!

procedure : tobject);

vardt: tdatetime;

beginif trystrtodatetime(,dt) thenshowmessage('is the date type')

elseshowmessage('Not a date type');

end;

Didn't have this problem! I don't know what version you use, d6, d7, d2005 don't have this problem!