Convert char array to a int number in C

I personally don’t like atoi function. I would suggest sscanf:

char myarray[5] = {'-', '1', '2', '3', '\0'};
int i;
sscanf(myarray, "%d", &i);

It’s very standard, it’s in the stdio.h library 🙂

And in my opinion, it allows you much more freedom than atoi, arbitrary formatting of your number-string, and probably also allows for non-number characters at the end.

EDIT I just found this wonderful question here on the site that explains and compares 3 different ways to do it – atoi, sscanf and strtol. Also, there is a nice more-detailed insight into sscanf (actually, the whole family of *scanf functions).

EDIT2 Looks like it’s not just me personally disliking the atoi function. Here’s a link to an answer explaining that the atoi function is deprecated and should not be used in newer code.

Related Posts:

  1. Returning an array using C
  2. How to copy a char array in C?
  3. How to empty a char array?
  4. C: warning: excess elements in array initializer; near initialization for ‘xxx’ ; expects ‘char *’, but has type ‘int’
  5. How do I check if a string contains a certain character?
  6. char *array and char array[]
  7. Return char[]/string from a function [duplicate]
  8. Return char[]/string from a function
  9. How to print a char array in C through printf?
  10. Excess elements in char array initializer error
  11. How to initialize array to 0 in C?
  12. How to do scanf for single char in C
  13. How to properly malloc for array of struct in C
  14. C char* to int conversion
  15. C subscripted value is neither array nor pointer nor vector when assigning an array element value
  16. struct has no member named
  17. Initializing array of structures
  18. What is the difference between array and enum in C ?
  19. Can I create an Array of Char pointers in C?
  20. Excess elements of scalar initializer for pointer to array of ints
  21. Why is the sizeof(int) == sizeof(long)?
  22. C char array initialization
  23. How to allocate array of pointers for strings by malloc in C?
  24. char array not assignable
  25. The difference between char * and char[] [duplicate]
  26. typedef fixed length array
  27. Pointer to 2D arrays in C
  28. Initializing 2D char array in C
  29. Convert Char to String in C
  30. What is an unsigned char?
  31. Get a substring of a char*
  32. How to convert a char array to a string?
  33. C: correct usage of strtok_r
  34. How do I create an array of strings in C?
  35. What does ** do in C language?
  36. Using Dynamic Memory allocation for arrays
  37. How do I create an array of strings in C?
  38. Finding the length of a Character Array in C
  39. How to clear all the elements of array in C?
  40. Zero an array in C code
  41. Passing an array by reference in C?
  42. Sign extend a nine-bit number in C
  43. Break statement not within loop or switch in C
  44. How to create an array of strings in C?
  45. C++ array assign error: invalid array assignment
  46. Cache Simulator in C
  47. Initialization from incompatible pointer type warning when assigning to a pointer
  48. expected expression before ‘{‘ token
  49. C Vector/ArrayList/LinkedList
  50. What is the difference between %f and %lf in C?
  51. What is stdin in C language?
  52. error: ‘for’ loop initial declarations are only allowed in C99 mode [duplicate]
  53. c – warning: implicit declaration of function ‘printf’
  54. char pointers: invalid conversion from ‘char*’ to ‘char’?
  55. How to compile makefile using MinGW?
  56. Portable way to check if directory exists [Windows/Linux, C]
  57. Incorrect checksum for freed object on malloc
  58. What is the difference between char array and char pointer in C?
  59. Simple way to check if a string contains another string in C?
  60. How to convert integer to char in C?
  61. Java Array Sort descending?
  62. Still Reachable Leak detected by Valgrind
  63. What is signed integer overflow?
  64. What does the term “empty loop” refer to exactly in C and C++?
  65. When to use const char * and when to use const char []
  66. Double pointer array in c++
  67. What do numbers using 0x notation mean?
  68. What integer hash function are good that accepts an integer hash key?
  69. Does stack grow upward or downward?
  70. X86 assembly – Handling the IDIV instruction
  71. error C2371: ‘functionname’ redefinition: different basic types
  72. Pause screen at program completion in C
  73. note: previous implicit declaration of ‘point_forward’ was here
  74. What exactly is meant by “de-referencing a NULL pointer”?
  75. How can I find the number of elements in an array?
  76. Array type char[] is not assignable
  77. getc() vs fgetc() – What are the major differences?
  78. Can’t understand the working of getint() in C as per K&R
  79. Lua – Number to string behaviour
  80. Parameter name omitted error?
  81. Warning: comparison of distinct pointer types
  82. Realloc Invalid Pointer in C
  83. What tools are there for functional programming in C?
  84. In C, what exactly happens when you pass a NULL pointer to strcmp()?
  85. How to format strings using printf() to get equal length in the output
  86. Example of waitpid() in use?
  87. Invalid write of size 1
  88. How to solve static declaration follows non-static declaration in GCC C code?
  89. realloc(): invalid next size when reallocating to make space for strcat on char *
  90. Can a function return two values?
  91. How to know what the ‘errno’ means?
  92. Printf was not declared in this scope
  93. How to free memory from char array in C
  94. Can I get Unix’s pthread.h to compile in Windows?
  95. GCC: Array type has incomplete element type
  96. Process exited with return value 3221225477
  97. gdb: No symbol “i” in current context
  98. %p Format specifier in c
  99. “Nothing to be done for makefile” message
  100. What is the difference between signed and unsigned int

Leave a Comment