NSdata, NSString, Byte array, UIImage conversion, nsdatansstring

NSdata, NSString, Byte array, UIImage conversion, nsdatansstring

1. NSData and NSString

NSData-> NSString

NSString * aString = [[NSString alloc] initWithData: adataencoding: NSUTF8StringEncoding];

 

NSString-> NSData

NSString * aString = @ "1234 abcd ";

NSData * aData = [aString dataUsingEncoding: NSUTF8StringEncoding];

 

2. NSData and Byte

NSData-> Byte array

NSString * testString = @ "1234567890 ";

NSData * testData = [testString dataUsingEncoding: NSUTF8StringEncoding];

Byte * testByte = (Byte *) [testData bytes];

For (int I = 0; I <[testData length]; I ++)

Printf ("testByte = % d \ n", testByte [I]);

 

Byte array-> NSData

Byte byte [] = {, 21 };

NSData * adata = [[NSData alloc] initWithBytes: byte length: 24];

 

Byte array-> hexadecimal number

Byte * bytes = (Byte *) [aData bytes];

NSString * hexStr = @"";

For (int I = 0; I <[encryData length]; I ++)

{

NSString * newHexStr = [NSString stringWithFormat: @ "% x", bytes [I] & 0xff]; // hexadecimal number

If ([newHexStr length] = 1)

HexStr = [NSString stringWithFormat: @ "% @ 0% @", hexStr, newHexStr];

Else

HexStr = [NSString stringWithFormat: @ "% @", hexStr, newHexStr];

}

NSLog (@ "bytes hexadecimal number: % @", hexStr );

 

Hexadecimal number-> Byte array

Convert hexadecimal data into Byte Arrays

NSString * hexString = @ "3e435fab9c34891f"; // hexadecimal string

Int j = 0;

Byte bytes [128]; // Byte array of 3ds key, 128 bits

For (int I = 0; I <[hexString length]; I ++)

{

Int int_ch; // The hexadecimal number after the two hexadecimal numbers are converted.

 

Unichar hex_char1 = [hexString characterAtIndex: I]; // the first of the two hexadecimal numbers (high * 16)

Int int_ch1;

If (hex_char1> = '0' & hex_char1 <= '9 ')

Int_rectangle = (hex_char1-48) * 16; // 0 Ascll-48

Else if (hex_char1> = 'A' & hex_char1 <= 'F ')

Int_rectangle = (hex_char1-55) * 16; // Ascll-65 of

Else

Int_rectangle = (hex_char1-87) * 16; // Ascll-97 of

I ++;

 

Unichar hex_char2 = [hexString characterAtIndex: I]; // the second digit in the two hexadecimal numbers (low position)

Int int_ch2;

If (hex_char2> = '0' & hex_char2 <= '9 ')

Int_ch2 = (hex_char2-48); // 0 Ascll-48

Else if (hex_char1> = 'A' & hex_char1 <= 'F ')

Int_ch2 = hex_char2-55; // Ascll-65 for

Else

Int_ch2 = hex_char2-87; // a's Ascll-97

 

Int_ch = int_ch + int_ch2;

NSLog (@ "int_ch = % d", int_ch );

Bytes [j] = int_ch; // put the converted number into the Byte array

J ++;

}

NSData * newData = [[NSData alloc] initWithBytes: bytes length: 128];

NSLog (@ "newData = % @", newData );

 

3. NSData and UIImage

NSData-> UIImage

UIImage * aimage = [UIImage imageWithData: imageData];

 

// Example: extract the image from the local file sandbox and convert it to NSData

NSString * path = [[NSBundle mainBundle] bundlePath];

NSString * name = [NSString stringWithFormat: @ "ceshi.png"];

NSString * finalPath = [path stringByAppendingPathComponent: name];

NSData * imageData = [NSData dataWithContentsOfFile: finalPath];

UIImage * aimage = [UIImage imageWithData: imageData];

 

UIImage-> NSData

NSData * imageData = UIImagePNGRepresentation (aimae );