C++ :: How To Convert Unsigned Char To String
Oct 4, 2014How do I convert a variable of type unsigned char to string.
View 9 RepliesHow do I convert a variable of type unsigned char to string.
View 9 RepliesI have a bitmap header information in the struct
typedef struct tagBITMAPINFO {
BITMAPINFOHEADER bmiHeader;
RGBQUAD bmiColors[1];
} BITMAPINFO
The total size of this is 1080.
Now i want to convert this into a unsigned char pointer.
unsigned char * pBMPHeaderData;
I already got the raw image data in another unsigned char buffer.
unsigned char* pRawBMPData;
Now i want to make a complete BMP image by adding the header info and raw data into a new unsigned char pointer. For this i need to convert the BITMAPINFO struct into a unsigned char *
So the new buffer will be,
unsigned char * pCompleteBMPIMageData = pBMPHeaderData + pRawBMPData;
how to do this?
I need to convert a string IP to an unsigned int (uint32), but however solutions I've found elsewhere have not worked (such as `atoi`).
When using `(uint32)"54.171.82.217 ";` : [URL] ....
When using `atoi("54.171.82.217");`: [URL] .....
How can I correctly convert the string version of the IP to the uint32 type?
I have the following code, but it crashes on the "data = " line...
Code:
void Test(string& data) {
unsigned char* msg = (unsigned char*)malloc(MAX_LENGTH));
...
data = string(reinterpret_cast<const char*>(msg), MAX_LENGTH);
}
I know I could just return string, but what is wrong with this code that is making it crash?
I need to convert the bit representation of an unsigned char into a string.
so like 254 would be "11111111"
I'm having some trouble where no matter what number I try to convert I get 01111111.
string bin2string(unsigned char N) {
string sN(8,'0');
unsigned char X;
unsigned char Y = 0;
for(int i = 0; i < 8; i++){
[Code] ....
I have the following code which attempts to assign a u_int8 array of 256 to an unsigned char[256]:
Code:
unsigned char testData[256]=pSample->data;
I get the compilation error:
error C2440: 'initializing' : cannot convert from 'const uint8_t [256]' to 'unsigned char [256]'
What is the safe way to cast or convert here?
unsigned char key[32];
139 unsigned char rfseed[32];
173 f = fopen("/dev/urandom","rb");
174 fread(key,1,32,f);
175 fread(rfseed,1,32,f);
I am having problems copying outputs of the above code into other unsigned char other[32]. I need to keep the output of dev/urandom for backup. But, when I try to assign the values by memcpy(other, key, 32), the values do not match. The same problem happens by assigning values index by index in a loop.
Is there anyway to convert std::string to char*?
Like:
std::string x="hello world";
char* y=x;
I have this code working:
char tmp_wku[3];
tmp_wku[0]=0x01;
tmp_wku[1]=0x9D;
tmp_wku[2]=0x62;
char tmp_com[11];
[Code] ....
This sends the buffer to a LIN modem. My question is: can this be done better. If I have a astring of hex numbers like "09 98 88 55 42 FF 00 00 FF BD 89". How could I send this without manually makng a char with hex numbers?
Currently I have:
Code:
char my_array[4] = { '1', '2', '3', '4' };
how do I convert the above to a string of: "1234"
.I have this string that I need to convert into a 2d char array like this:
String str= "A,E,B,I,M,Y#N,R,C,A,T,S";
I know how to use delimiter and split string and I know how to convert but only from string to char[].I need something like this:
Input: String str= "A,E,B,I,M,Y#N,R,C,A,T,S";
Output: [A] [E] [B] [I] [M] [Y][N] [R] [C] [A] [T] [S]
How do I convert a string of unknown length to a char array? I am reading strings from a file and checking if the string is a Palindrome or not. I think my palindrome function is correct, but do I do something like char [] array = string.length(); ??
#include <iostream>
#include <fstream>
#include <string>
#include <cctype>
[Code].....
I need to find some sort of method to convert a series of char variables to a string, to be shown in a label. I've searched for two days and experimented myself just as long, and the closest I've gotten simply puts ASCII values into the string with the following command:
label1 -> Text = System::Convert::ToString(fdp8), System::Convert::ToString(fdp7),
System::Convert::ToString(fdp6), System::Convert::ToString(fdp5),
System::Convert::ToString(fdp4), System::Convert::ToString(fdp3),
System::Convert::ToString(fdp2), System::Convert::ToString(fdp1);
fdp1-fdp8 are all char variables.
how to convert char to string or vice versa,, Also make a program in which we convert a char into string ?
Conversion Char array to String
when you convert 1.7 to unsigned int, it becomes 1 or 2?
View 9 Replies View RelatedHow do I print an unsigned char in c++? E.g.
unsigned char a[100] = "acdef";
wprintf(L"a is %u
", a);
wcout << "a is " << a << endl;
gives
a is 2880488
a is 002BF3E8
and not
a is acdef
a is acdef
??
what is the difference between unsigned char and char?
I am having some trouble performing this. I am not sure, if my unsigned char arrays are null terminated, but I don't think so. Here is my code: They are supposed to be byte arrays of size 16.
int setkey(unsigned char* ky) {
printf("INSIDE POLY-DEL ... key byte array passed in HEX:
");
int i;
for (i = 0; i < (int)16; i++)
[Code] .....
How do you use char instead of unsigned to calculate numbers? This is using char only and nothing else.
Step 1: I ask the user to enter a number.
Step 2: User enters a number.
Step 3: Number user entered is going to be that number squared or cubed or w/e.
For example;
"Enter a number: " 3
" Number you entered multiplied four times: " 81 (Since (3)*(3)*(3)*(3) = 81)
Another example;
"Enter a number: " 5
" Number you entered multiplied four times: " 625 (Since (5)*(5)*(5)*(5) = 625)
Code:
Char num;
cout << "Enter a number";
cin >> num;
cout << "Number you entered multiplied four times: " << (num)*(num)*(num)*(num) << endl;
i wish to generate all possible key combinations ranging:
HEX: "0F FF FF FF FF FF FF FF" TO HEX: FF FF FF FF FF FF FF FF
i also test each key after incrementing by 1, for test i want the key to be a an unsigned char[8]
key start rang and end range can be initialize/declare in any format.
Problem is if :
unsigned char key[] = {0x0F,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF};
then i can not increment this key by +1 , though if i initialize this key in decimal as:
unsigned long long key = 1152921504606846975;
then i can increment the key in for loop by key++ but then i cant convert it back into unsigned char array
i want to achieve something like this :
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
unsigned char key[] = {0x0F,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF};
int main()
{
[code]...
In my programer i also have function that test each key but key has to be unsigned char...
I came across some code and it's not clear why it is casting an unsigned char * to another pointer type only to free it right after. Here are the relevant structures:
Code:
struct _Edje_Message {
Edje *edje;
Edje_Queue queue;
Edje_Message_Type type;
int id;
unsigned char *msg;
[Code] .....
As you can see, _Edge_Message has a *msg field, but in the function below, they cast it to the other two structure types inside the case blocks of the switch statement only to free it. What is the point or advantage of doing this?
Code:
void
_edje_message_free(Edje_Message *em) {
if (em->msg) {
int i;
switch (em->type) {
[Code] ......
Got something like the following. A button that read characters from a thrid party tool and sends it to a listbox. But the contant is not readable.
Code:
void dlg::sendtolistbox() {
unsigned char buf[250];
thirdparty.GetData(buf, len);
Sendmessage(hndl, listboxupdate,0 , (LPARAM)buf);
}
void Mydlg::UpdateListBox(wparam a,laparm b) {
m_listbox.AddString((LPCTSTR)b);
}
The characters show up in the list box as short unreadable characters. like it is chopped.
If i change to : Sendmessage(hndl, listboxupdate,0 , (LPARAM)&buf[15]);
Then I can see readable valid strings of up to 50 characters and then empty unreadable characters afterwards. I tried all kinds of things , including using CString, still did not work.
I am writing a program where I need to read a byte of char data and convert it into a text string of binary data that represents the hex value...
i.e. The char byte is 0x42 so I need a string that has 01000010 in it. I've written the following subroutine....
------------- My Subroutine ----------------------------------------------------------------------
void charbytetostring(char input, char *output){
int i, remainder;
char BASE=0x2;
int DIGITS=8;
char digitsArray[3] = "01";
[Code] ....
When I submitted the byte 0x42 to the subroutine, the subroutine returned to the output variable 01000010... Life is good.
The next byte that came in was 0x91. When I submit this to the subroutine I get garbage out.
I am using a debugger and stepped through the subroutine a line at a time. When I feed it 0x42 I get what I expect for all variables at all points in the execution.
When I submit 0x91 When the line remainder = input % BASE; gets executed the remainder variable gets set to 0xFFFF (I expected 1). Also, when the next line gets executed..
input = input / BASE; I get C9 where I expected to get 48.
My question is, are there data limits on what can be used with the mod (%) operator? Or am I doing something more fundamentally incorrect?
I have an embedded microcontroller system communicating with a similar system by radio. The api for the radio requires data to be transmitted as an unsigned char array. It will always transmit a positive integer in the range 0 to 255.When I receive the data I am having difficult in extracting this positive integer.
Code:
unsigned char rxData[4]={'1','2','3',''};
int inVal=0;
//want to assign inVal whatever number was transmitted
E.g. 123
I've been at this for a week and have tried at least 10 different approaches including the use of the atoi(), copying the absolute value of each element of rxData into another char array, reinterpret_cast, and others.
I need fastest method to reverse order of bytes in my char array.
For example i have:
unsigned char buf[8];
// consider data stored in buf is 88 77 66 55 44 33 22 11
// how to reverse it to: 11 22 33 44 55 66 77 88
// currently i can do it by equal assignment , i make another buf like:
unsigned char buf_ok[8];
[Code] ....
// This does reverse the bytes as i want but its very slow , i am looking for fast method ..
I'm having a pretty weird problem. I've created an unsigned char array for an image buffer:
buffer_rgb = new unsigned char[_w * _h * 3];
memset(buffer_rgb, 0x0, sizeof(unsigned char)* _w * _h * 3);
And I add pixel color values to it like so:
buffer_rgb[i] = ((unsigned char)(col[0] * 255));
buffer_rgb[i + 1] = ((unsigned char)(col[1] * 255));
buffer_rgb[i + 2] = ((unsigned char)(col[2] * 255));
Where col is a 'vec4' struct with a double[4] with values between 0 and 1 (this is checked and clamped elsewhere, and the output is safely within bounds). This is basically used to store rgb and intensity values.
Now, when I add a constant integer as a pixel value, i.e.:
buffer_rgb[i] = ((unsigned char)255;
Everything works as it should. However, when I use the above code, where col is different for every sample sent to the buffer, the resulting image becomes skewed in a weird way, as if the buffer writing is becoming offset as it goes.
These two images illustrate the problem:
tomsvilans.com/temp/140803_render_skew.png
tomsvilans.com/temp/140803_render_noskew.png
You can see in the 'noskew' image all pixels are the same value, from just using an unchanging int to set them. It seems to work with any value between 0-255 but fails only when this value is pulled from my changing col array.
Whole function is here:
// adds sample to pixel. coordinates must be between (-1,1)
void Frame::addSample(vec4 col, double contrib, double x, double y) {
if (x < -1 || x >= 1 || y < -_aaspect || y >= _aaspect) {
[Code] .....
I have a file which contains a year and the name of an associated file to be read. I need to extract the data in the txt file and perform some calculations.
( year data file)
2004 2004data.txt
2005 2005data.txt
2006 2006data.txt
Here is what I do. I first declare "char yeardata" and then pass "2004data.txt" to it. Then I call yeardata in ifstream to extract the data inside the file "2004data.txt". The problem is that char yeardata is not constant so I cannot pass the file to it. It doesn't work if I change "char yeardata" to "const char yeardata".
Code:
int oldnewcomp_temp(char* lcfile) {
using namespace std;
int year;
char yeardata;
[Code] ....