References, Pointers and Constants: Difference between revisions
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To declare a constant -- a value that cannot be changed<br> | To declare a constant -- a value that cannot be changed<br> | ||
Has no effect for passing values to a function or from returning values from a function | Has no effect for passing values to a function or from returning values from a function | ||
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|char []<br> | | | ||
char []<br> | |||
int []<br> | int []<br> | ||
double [] | double [] | ||
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To return a dynamically-allocated array from a function.<br> | To return a dynamically-allocated array from a function.<br> | ||
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const char *<br> | const char *<br> | ||
const int *<br> | const int *<br> | ||
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To return a pointer to a constant value<br> | To return a pointer to a constant value<br> | ||
To pass a pointer to a constant value to a function | To pass a pointer to a constant value to a function | ||
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To pass a value to a function which will be set by the function (without using a pointer) | To pass a value to a function which will be set by the function (without using a pointer) | ||
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char * &<br> | char * &<br> | ||
int * &<br> | int * &<br> | ||
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To pass a pointer to a function where the function will set the pointer (either by calling new or by assigning to the pointer | To pass a pointer to a function where the function will set the pointer (either by calling new or by assigning to the pointer | ||
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char * const<br> | char * const<br> | ||
int * const<br> | int * const<br> | ||
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When you want to point to a specific value. Allows to you to change the data that is pointed to, but you can't change the pointer | When you want to point to a specific value. Allows to you to change the data that is pointed to, but you can't change the pointer | ||
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!style="color:#ffb900"|C++ Code | |||
!style="color:#ffb900"|What It Means | |||
!style="color:#ffb900"|When To Use It | |||
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Revision as of 07:30, 14 October 2008
Simple C++ Data Types
C++ Code | What It Means | When To Use It |
---|---|---|
char |
Single (scalar) value (character, integer, floating point number) |
To store data |
const char |
Constant value |
To declare a constant -- a value that cannot be changed |
char [] |
Array (vector) of values |
To store the same type of data together |
const char [] |
Constant array of values |
To declare an array of constant values (no element in the array can be changed) |
char * |
Pointer to a single value or an array of values |
To store a string (char *) |
const char * |
Pointer to a constant value |
When you don't want the value at the pointer to be changed, but you can still change the pointer |
char & |
Reference to a value |
To pass a value to a function which will be set by the function (without using a pointer) |
char * & |
Reference to a pointer |
To pass a pointer to a function where the function will set the pointer (either by calling new or by assigning to the pointer |
char * const |
Constant pointer |
When you want to point to a specific value. Allows to you to change the data that is pointed to, but you can't change the pointer |
C++ Code | What It Means | When To Use It |
---|---|---|
1 | 2 | 3 |