iOS socket常用数据类型转换

int -> data

/** int -> data */
+ (NSData *)intToData:(int)value
{
    Byte byte[4] = {};

    byte[0] =  (Byte) ((value>>24) & 0xFF);
    byte[1] =  (Byte) ((value>>16) & 0xFF);
    byte[2] =  (Byte) ((value>>8) & 0xFF);
    byte[3] =  (Byte) (value & 0xFF);
    NSData *data = [NSData dataWithBytes:byte length:4];

    return data;
}

long -> data

/** long -> data */
+ (NSData *)longToData:(long)value
{
    Byte byte[8] = {};

    for (int i = 0; i < 8; i ++) {
        byte[i] = (Byte) ((value >> (56 - 8 * i)) & 0xFF);
    }
    NSData *data = [NSData dataWithBytes:byte length:8];
    return data;
}