C++ :: Char Array To String - String Becomes Garbage
Apr 20, 2013
I'm trying to "tokenize" a string using std::string functions, but I stored the text in a char array. When I try to convert it to a string, the string has the first character right but the rest is garbage.
// Get value from ListBox.
char selectedValue[256];
memset(selectedValue, NULL, 256);
SendMessage(GetDlgItem(hWnd, IDC_LB_CURRENTSCRIPT), LB_GETTEXT, selectedIndex, (LPARAM)selectedValue);
// Convert to string.
string val(selectedValue);
I wrote a program that tries to tokenize a mathematical expression, inserting the tokens in a list of strings. The list is as follows:
typedef struct listOfStrings { char **array; int size; } ListOfStrings;
There is even a function to initialize the listOfStrings. The thing is: I'm printing a token every time it is complete and every time it is inserted in the list. The output is okay. However, when all tokens are processed and I call function print_list_of_strings to print the tokens again, the first token is printed with a leading garbage value if the input for the program is "3 + 4 * 2 / ( 1 - 5 ) ^ 2 ^ 3". How is this possible? The code for printing the list is as follows:
void print_list_of_strings( const ListOfStrings *const lPtr ) { int i; int numberOfElements = lPtr->size; if ( numberOfElements != 0 ) { for ( i = 0 ; i < numberOfElements ; ++i ) {
[Code] ....
The list just prints --- if it's empty, although this isn't the case for the program I'm writing. Also, if the input is "1 + 2", everything goes fine. The code for inserting at the list is:
int insert_at_end_of_list_of_strings( ListOfStrings *lPtr, const char *const str ){ int lengthOfStr = strlen( str ); int numberOfElements = lPtr->size; if ( ( ( *( lPtr->array + numberOfElements ) ) = ( char * )malloc( ( lengthOfStr + 1 ) *
In this program, I have to ask the user for an employee, then the program will check to see if the file for that employee exist, if it doesnt then it will automatically create the file.
ReadNew function reads the file....check to see if it exist
CreateNew function creates a new file.
In my code I have no problem with the first part of reading file.. and my createnew function works in other programs where I am asking for input of file name to create the file name. However in this code I cannot figure how to automatically pass the input filename from the ReadNew function to the CreateNew function. I can't ask the user to enter the name a second time, so I have to pass the input filename into both functions. Here is my code.
Code:
//Create a file, append to it, and read it. #include <iostream> #include <fstream> #include <string.h> #include <stdio.h> using namespace std; char filename[256]; string n; string filelist; void CreateNew(ofstream & FileNew);
I have a text file with state names, and state abbreviations, thusly:
ALASKA AK ARKANSAS AR ..and so on.
I have to load the abbreviations ONLY from the file into an array of char[ - (already done and tested).
I have to get a 2 char abbreviation as a string,then test it against the state array to make sure it is a valid abbreviation. As it stands, my test is never finding an invalid abbreviation..
Here is where I get the input:
void getState() { char state[10]; getString("Please enter the state as a 2 char abbreviation:",state,10); printf("State Entered:%s", state); validState(state);
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(); ??
I am new to C++ and I have a two player word guessing game working well. However, I would like to be able to validate whether the word entered by player 1 is a completely alphabetic word using isalpha.
The error I am getting right now is as follows:
"error: array must be initialized with a brace-enclosed initializer char str[100]=hiddenwordtwo;"
I am trying to store each char of a string(string a ="1100") into a byteArray ( byte[] byteArray = new byte[4]. its not showing any error but its storing like below:
I don't know why but its replacing 1 with 49 and 0 with 48.what am I doing wrong or how to do this?
my code is as below
byte[] byteArray = new byte[4];)/> int binArrayAdd = 0; string a ="1100"; foreach (char Character in a) { byteArray [binArrayAdd] = Convert.ToByte(Character); binArrayAdd++; }
I have program where i have to check to see if file exist, if it does not then it needs to be created. SO I have a read file that works fine, if th efile exist it reads whats in it, if it does it says the file does not exist. Now Im trying to creata function that creates the file if it doesnt exist. so in my read function when the person enters the name of the file to be checked for..I pass that name to a variable called name..Hoping that I could then pass it into my create file function if it does not exist..and use that variable to pass the name they entered into the createfile array..called filename.. but I am having trouble because i get error when i try to pass from a string name to char array.. even when I change the varialbe name to char, or char [256] it will not work.. I try to fing a way to convert th string to a char using the strncopy function but still no dice..here the code i have for the createfile funciton
I have the codes for such a problem where, to create a program that counts how many times the second string appears on the first string. Yes it counts if you put 1 letter only, but if you put 2, it is an error. As an example. If the first string is Harry Partear, and the second string is ar, it must count as 3. Here's the code:
Code:
#include <iostream> #include <conio.h> using namespace std; int main ()
I have this function in a class: and a private declaration: how can I copy the parameter "ProductName" to allowedProductName. I tried all combination and I can't get it to compile.
Here STRING is a user defined class. how to assign a constant char array "FOOBAR" to string object? Copy constructor need to be same class type as parameter. and overloading assignment operator also need to be same class type. I think 'friend' can let pass another type of object rather than STRING to do operation on overloaded '=' operator. How could it be done if it is possible at all?
This code ran well until i added in the ToLower function which is supposed to convert the char array string to lower case (based off ascii strategy -32). correct this function so it converts string to lower case and doesn't get errors.
#include <iostream> #include <string> using namespace std; const int MAX = 81; //max char is sting is 80 void ToLower(char s[]); int main(){ string y_n;
I have been assigned the following task and I am having difficulty in getting it to compile. The compiler is stopping at line 27 but I don't no what the error is.
The task is as follows:
Write two functions with the following function prototypes:
int my string len(char str[]) void my string cat(char dest[], char src[], int dest size)
Both functions should take zero-terminated strings as input. The first function should return the length of the string to the calling function. The second function should take a source and a destination string and the total size of the array pointed to by dest. It should then concatenated the source string onto the end of the destination string, if and only if the destination string has the capacity to store both strings. If the destination string does not have the capacity it should not alter either, print and error, and return to the calling function. Demonstrate the use both the above functions by using them in a program in which you initialise two character arrays with two strings, print out their length, print out the combined length, and print out the combined string
And this is my code so far:
/* A program to demonstrate string concatenation */
#include <iostream> #include <string.h> using namespace std; int my_string_len(char str[]){ // function to calculate length of a chracter array int len = 0;
Very new to programming, and I know that there must be another way on inputting a string into each array cells not by just inputting it one by one, but as a whole. My code at the meantime is: [URL]
/*assume array is already initialized and declared and is of array type string.*/
int i = 2; int j = 1; string newvalue; cout<<"Current value at array[i][j] is "<<array[i][j]<<endl; cout<<"Enter new value "<<endl; cin>>newvalue; array[i][j]= newvalue; //PROBLEM IS IN THIS LINE. cout<<endl; cout<<array[i][j]<<endl;
I'm having lots of trouble with storing a cin string text into a string array. It just seem that after I cin newvalue, the program crashes. Is this way of storing it considered illegal? I'm just a beginner with 5 months of coding experience in C++.
