مجموعه برنامه‌ های نوشته شده به زبان جاوا

[dasssnj]

تبدیل string به int با الگوریتم خودم.

public static int strToint(String e) throws NumberFormatException {

    if (e == null || e.length() < 1 || e.equals("")) //string moshkel dare

        throw new NumberFormatException("String : " + e + " is corrupt !");

     

    char[] ch = e.toCharArray();

    boolean negative = false; //manfi

    int len = ch.length; // toole adad

    int[] i = new int[len]; //araye adad

    short j, k; // adad halghe ha

    int result = 0; //javab

    if (ch[0] == '-') { //manfi

        if (e.length() == 1) 

            throw new NumberFormatException("String : " + e + " is corrupt !");

         

        negative = true; // manfi mishe

        ch = e.substring(1).toCharArray();

        len = ch.length;

    } else if (ch[0] == '+') { //mosbat

        if (e.length() == 1) 

            throw new NumberFormatException("String : " + e + " is corrupt !");

        ch = e.substring(1).toCharArray();

        len = ch.length;

    }

 

    for (j = 0; j < len; j++) {

        if (ch[j] < '0' || ch[j] > '9') // bayad beine 0 ta 9 bashe

            throw new NumberFormatException("String : " + e + " Not a Number !");

        i[j] = ch[j] - 48; // az char ke adad bashe 48 ta kam koni mishe int

        for (k = 0; k < len - (j + 1); k++) 

            i[j] *= 10; //sefr ha ra mizaram ba zarb dar 10

         

        result += i[j]; // hala jam mikonam

        if (result < 0) //aslan nabayad manfi bashe

        {

            if (result == -2147483648 && negative) {//No problem (-|0)

                // irad az man nist . system manfi bar migardoone . baray hamin in shart lazeme

            } else //adad bozorg tar az int

            {

                throw new NumberFormatException("Number : " + e + " is out of range for int! ");

            }

        }

    } 

    return negative ? -result : result; // manfi bashe ya mosbat

}