How to String to Validate only Numbers

1) using String to Validate only Numbers Regular Expression

static void THK_isNumericForRegularExpression(Args _args)

{

    TextBuffer  txt = new TextBuffer();

    str         msg = "9879q7897";

;

    txt.setText(msg);

    txt.regularExpressions(true);   // activate regular expr in search

    setprefix(msg);

    // Regular expression to validate only digits

    if (txt.find("^[0-9]+$"))

    {

        info("Yes,string contains only numbers");

    }

    else

        checkFailed("No");

}

2) build - in method
static void THK_isNumeric(Args _args)
{
    str     st = "1234we7878899";
   
boolean isNumeric(str StrNumVar)
{
    boolean ret = true;
    int     m,n;
    str     s = strkeep(StrNumVar,"1234567890");
;
    m   = strlen(StrNumVar);
    n   = strlen(strkeep(StrNumVar,"1234567890"));
    ret = m == n;
 
    return ret;
}

boolean  THK_validNumbers(str _text)
{
    int     counter, textLen = strlen(_text);
    Phone   validNumbers = '0123456789';
    ;

    for(counter = 1; counter <= textLen; counter ++)
    {
        if(!strfind(substr(_text,counter,1), validNumbers, 1, 10))
        {
            return false;
        }
    }
    return true;
}

;
    info(queryValue(isNumeric(st)));
    info(queryValue( THK_validNumbers (st)));
}