字符串转化成十六进制数

unsigned int StringToHex(char* str,int length)

{

    int i;

    int result=0;

    for(i=0; i<length; i++)

    {

        if((str[i]>='a') && (str[i]<='f')) {

            result = result*16 + str[i] - 'a' + 10;

        }

        if((str[i]>='A') && (str[i]<='F')) {

            result = result*16 + str[i] - 'A' + 10;

        }

        if((str[i]>='0') && (str[i]<='9')) {

            result = result*16 + str[i] - '0';

        }

    }

    return result;

}