最近項目中要用到socket通訊，由于涉及到組包問題，所以需要數據類型之間的來回轉換，現在分享出來

如果想要請教Socket的問題請留言，我會隨時回答的

1. int類型轉16進制hexstring

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//int?轉16進制??

-?(NSString?*)hexFromInt:(NSInteger)val?{??

????return?[NSString?stringWithFormat:@"%X",?val];??

}??

?

2.16進制轉換為NSData

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+?(NSData?*)dataFromHexString:(NSString?*)hexString??

{??

????NSAssert((hexString.length?>?0)?&&?(hexString.length?%?2?==?0),?@"hexString.length?mod?2?!=?0");??

????NSMutableData?*data?=?[[NSMutableData?alloc]?init];??

????for?(NSUInteger?i=0;?i<hexString.length;?i+=2)?{??

????????NSRange?tempRange?=?NSMakeRange(i,?2);??

????????NSString?*tempStr?=?[hexString?substringWithRange:tempRange];??

????????NSScanner?*scanner?=?[NSScanner?scannerWithString:tempStr];??

????????unsigned?int?tempIntValue;??

????????[scanner?scanHexInt:&tempIntValue];??

????????[data?appendBytes:&tempIntValue?length:1];??

????}??

????return?data;??

}??

3.NSData轉16進制

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+?(NSString?*)hexStringFromData:(NSData?*)data??

{??

????NSAssert(data.length?>?0,?@"data.length?<=?0");??

????NSMutableString?*hexString?=?[[NSMutableString?alloc]?init];??

????const?Byte?*bytes?=?data.bytes;??

????for?(NSUInteger?i=0;?i<data.length;?i++)?{??

????????Byte?value?=?bytes[i];??

????????Byte?high?=?(value?&?0xf0)?>>?4;??

????????Byte?low?=?value?&?0xf;??

????????[hexString?appendFormat:@"%x%x",?high,?low];??

????}//for??

????return?hexString;??

}??

4.NSString轉int類型

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int?a?=?[aStrinng??intValue];??

5.uint8轉NSData(占兩位)

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+?(NSData?*)byteFromUInt8:(uint8_t)val??

{??

????NSMutableData?*valData?=?[[NSMutableData?alloc]?init];??

??????

????unsigned?char?valChar[1];??

????valChar[0]?=?0xff?&?val;??

????[valData?appendBytes:valChar?length:1];??

??????

????return?[self?dataWithReverse:valData];??

}??

6.uint16 轉NSData（占四位）

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+?(NSData?*)bytesFromUInt16:(uint16_t)val??

{??

????NSMutableData?*valData?=?[[NSMutableData?alloc]?init];??

??????

????unsigned?char?valChar[2];??

????valChar[0]?=?0xff?&?val;??

????valChar[1]?=?(0xff00?&?val)?>>?8;??

????[valData?appendBytes:valChar?length:2];??

??????

????return?[self?dataWithReverse:valData];??

}??

7.Uint32 轉NSData（占八位）

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+?(NSData?*)bytesFromUInt32:(uint32_t)val??

{??

????NSMutableData?*valData?=?[[NSMutableData?alloc]?init];??

??????

????unsigned?char?valChar[4];??

????valChar[0]?=?0xff?&?val;??

????valChar[1]?=?(0xff00?&?val)?>>?8;??

????valChar[2]?=?(0xff0000?&?val)?>>?16;??

????valChar[3]?=?(0xff000000?&?val)?>>?24;??

????[valData?appendBytes:valChar?length:4];??

??????

????return?[self?dataWithReverse:valData];??

}??

?

8.NSString 轉NSData

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NSData?*data?=?[aString??dataUsingEncoding:NSUTF8StringEncoding];//?通過utf-8轉為data??

9.NSData轉Uint8

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+?(uint8_t)uint8FromBytes:(NSData?*)fData??

{??

????NSAssert(fData.length?==?1,?@"uint8FromBytes:?(data?length?!=?1)");??

????NSData?*data?=?fData;??

????uint8_t?val?=?0;??

????[data?getBytes:&val?length:1];??

????return?val;??

}??

10.NSData轉Uint16

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+?(uint16_t)uint16FromBytes:(NSData?*)fData??

{??

????NSAssert(fData.length?==?2,?@"uint16FromBytes:?(data?length?!=?2)");??

????NSData?*data?=?[self?dataWithReverse:fData];;??

????uint16_t?val0?=?0;??

????uint16_t?val1?=?0;??

????[data?getBytes:&val0?range:NSMakeRange(0,?1)];??

????[data?getBytes:&val1?range:NSMakeRange(1,?1)];??

??????

????uint16_t?dstVal?=?(val0?&?0xff)?+?((val1?<<?8)?&?0xff00);??

????return?dstVal;??

}??

11.NSData轉Uint32

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+?(uint32_t)uint32FromBytes:(NSData?*)fData??

{??

????NSAssert(fData.length?==?4,?@"uint32FromBytes:?(data?length?!=?4)");??

????NSData?*data?=?[self?dataWithReverse:fData];??

??????

????uint32_t?val0?=?0;??

????uint32_t?val1?=?0;??

????uint32_t?val2?=?0;??

????uint32_t?val3?=?0;??

????[data?getBytes:&val0?range:NSMakeRange(0,?1)];??

????[data?getBytes:&val1?range:NSMakeRange(1,?1)];??

????[data?getBytes:&val2?range:NSMakeRange(2,?1)];??

????[data?getBytes:&val3?range:NSMakeRange(3,?1)];??

??????

????uint32_t?dstVal?=?(val0?&?0xff)?+?((val1?<<?8)?&?0xff00)?+?((val2?<<?16)?&?0xff0000)?+?((val3?<<?24)?&?0xff000000);??

????return?dstVal;??

}??

12.NSData轉Byte

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uint8_t?byteArray[[data?length]];??

???

?[data?getBytes:&byteArray?length:[data?length]];??

???

??

?for?(int?i?=?0;?i?<?[data?length]?;?i++?)?{??

?????Byte?byte?=?byteArray[i];??

?????NSLog(@"--byte%x",byte);??

?}??

?

13.NSData的拼接

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[data1?appendData:data2];??

?

14.NSData轉int (用CFSwapInt32BigToHost)

?

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NSData?*data4?=?[completeData?subdataWithRange:NSMakeRange(0,?4)];??

int?value?=?CFSwapInt32BigToHost(*(int*)([data4?bytes]));??

?

以上可能會用到的反轉字節序列代碼

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+?(NSData?*)dataWithReverse:(NSData?*)srcData??

{??

????//????NSMutableData?*dstData?=?[[NSMutableData?alloc]?init];??

????//????for?(NSUInteger?i=0;?i<srcData.length;?i++)?{??

????//????????[dstData?appendData:[srcData?subdataWithRange:NSMakeRange(srcData.length-1-i,?1)]];??

????//????}//for??

??????

????NSUInteger?byteCount?=?srcData.length;??

????NSMutableData?*dstData?=?[[NSMutableData?alloc]?initWithData:srcData];??

????NSUInteger?halfLength?=?byteCount?/?2;??

????for?(NSUInteger?i=0;?i<halfLength;?i++)?{??

????????NSRange?begin?=?NSMakeRange(i,?1);??

????????NSRange?end?=?NSMakeRange(byteCount?-?i?-?1,?1);??

????????NSData?*beginData?=?[srcData?subdataWithRange:begin];??

????????NSData?*endData?=?[srcData?subdataWithRange:end];??

????????[dstData?replaceBytesInRange:begin?withBytes:endData.bytes];??

????????[dstData?replaceBytesInRange:end?withBytes:beginData.bytes];??

????}//for??

??????

????return?dstData;??

}?

總結

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