easiest way to check integer

[cynikern]

how can I easy check if an ansistring can be an integer value?

i want the only input in a stringgrid cell to be 0-9.

i hope you could understand what i wanted to say, my english is not very good.

thanks for your help in advance

 

[onrdbandit]

Howdy,

AnsiStrings have a ToFloat() method that you can use. Something like this will do the trick:

//Save the string as a float
float SomeVariable = TheString.ToFloat();

//Test if the float is a decimal or an int
if((int)SomeVariable == SomeVariable)
{
//Do whatever you want to do
}


This code takes your AnsiString (TheString) can saves it in SomeVariable as a floating point decimal, then tests if that float equals itself once typecasted as an integer.

Some AnsiStrings can't be evaluated for a float, and the only way I know to tell if a string can be evaluated as a float is to iterate through each character and test it. If you need me to do so I could post a sample...

Hope I could help,
onrdbandit

 

[butthead]

int z = atoi (string.c_str ());

tomcruz.net

 

[Supernat03]

try
{
int x = MyString.ToInt();
float y = MyString.ToDouble();
// check valid range.
// set the database or whatever to new value.
}
catch (...)
{
// Code that says x wasn't an int or y wasn't a double.
}

Chris

 

[cynikern]

thanks for all your help guys it solved my problem

//cynikern

 

[LastCyborg]

try this too
on KeyDown or KeyPress event
if (((Key <'0') && (Key >'9')) || Key != 8)
Key = 0;

check the event OnChange too to prevent insertions from mouse



---LastCyborg---