#import <Foundation/Foundation.h>
@interface ByteUnit : NSObject
//返回指定字节的10进制数
+(unsigned long)subDataLength:(NSData*)_didReadData startCount:(int)_startCount lenghtCount:(int)_lengthCount;
//将字节转为字符串形式
+(NSString *)byteToString:(NSData *)data startCount:(int)_startCount lenghtCount:(int)_lengthCount;
//字符串转字节数据
+(NSData*)stringToByte:(NSString*)string;
@end
//
// ByteUnit.m
// SmartHomeWIFI
//
// Created by 深圳市 秀软科技有限公司 on 14-2-18.
// Copyright (c) 2014年 huhuaxiang. All rights reserved.
//
#import "ByteUnit.h"
@implementation ByteUnit
//获取数据长度。固定标准 4控制+4长度
+(unsigned long)subDataLength:(NSData*)_didReadData startCount:(int)_startCount lenghtCount:(int)_lengthCount
{
unsigned long loc_length = 0;
if (_didReadData.length >= _startCount+_lengthCount) {
Byte *testByte = (Byte *)[_didReadData bytes];
NSString *loc_string = @"";
for (int i = 0 ; i <_lengthCount; i++) {
unsigned long loc_length1 = testByte[_startCount+i];
loc_string =[NSString stringWithFormat:@"%@%.2lx",loc_string,loc_length1];
//[[NSString stringWithFormat:@"%.2lx",loc_length1] stringByAppendingString:loc_string];//反
// NSLog(@"hejiang:%@",loc_string);
}
// unsigned long loc_length1 = testByte[4];
// unsigned long loc_length2 = testByte[5];
// unsigned long loc_length3 = testByte[6];
// unsigned long loc_length4 = testByte[7];
// NSString *loc_string = [NSString stringWithFormat:@"%.2lx%.2lx%.2lx%.2lx",loc_length4,loc_length3,loc_length2,loc_length1];
unsigned long red = strtoul([loc_string UTF8String],0,16);
loc_length = red;
}
return loc_length;
// if(_lengthCount==2)
// return htons(loc_length);
// else
// return htonl(loc_length);
}
+(NSString *)byteToString:(NSData *)data startCount:(int)_startCount lenghtCount:(int)_lengthCount
{
/*
NSData *dataT=[data subdataWithRange:NSMakeRange(_startCount, _lengthCount)];
NSString *str=[[NSString alloc]initWithData:dataT encoding:NSUTF8StringEncoding];
return str;
*/
NSString *loc_string = @"";
if (data.length >= _startCount+_lengthCount) {
Byte *testByte = (Byte *)[data bytes];
for (int i = 0 ; i <_lengthCount; i++) {
unsigned long loc_length1 = testByte[_startCount+i];
loc_string = [NSString stringWithFormat:@"%@%.lx",loc_string,loc_length1];
}
}
return loc_string;
}
+(NSData*)stringToByte:(NSString*)string
{
NSString *hexString=[[string uppercaseString] stringByReplacingOccurrencesOfString:@" "withString:@""];
if ([hexString length]%2!=0) {
return nil;
}
Byte tempbyt[1]={0};
NSMutableData* bytes=[NSMutableDatadata];
for(int i=0;i<[hexString length];i++)
{
unichar hex_char1 = [hexString characterAtIndex:i]; ////两位16进制数中的第一位(高位*16)
int int_ch1;
if(hex_char1 >= '0' && hex_char1 <='9')
int_ch1 = (hex_char1-48)*16; //// 0 的Ascll - 48
else if(hex_char1 >= 'A' && hex_char1 <='F')
int_ch1 = (hex_char1-55)*16; //// A 的Ascll - 65
else
return nil;
i++;
unichar hex_char2 = [hexString characterAtIndex:i]; ///两位16进制数中的第二位(低位)
int int_ch2;
if(hex_char2 >= '0' && hex_char2 <='9')
int_ch2 = (hex_char2-48); //// 0 的Ascll - 48
else if(hex_char2 >= 'A' && hex_char2 <='F')
int_ch2 = hex_char2-55; //// A 的Ascll - 65
else
return nil;
tempbyt[0] = int_ch1+int_ch2; ///将转化后的数放入Byte数组里
[bytes appendBytes:tempbyt length:1];
}
return bytes;
}
@end
