When using the delete operator in C++, deleting pointers should be done with caution. Pointers are a powerful tool, and as with any tool, there is potential for misuse. In this guide, you will discover the fundamentals of using the delete operator on pointers and gain practical tips and guidelines for best practices.
What is the Delete Operator?
The delete operator is an operator used for deleting pointers in C++. Its purpose is to free the memory allocated for an object that was previously created using new, and it can be used on both heap objects and member objects. Delete can take a single parameter or an array of parameters, and will call the destructor of the object (or objects) before freeing the memory.
When Should You use the Delete Operator?
If you are allocating memory with new and you wish to discard the memory and its content, you should always use the delete operator. Failure to use delete after allocating memory with new will result in a memory leak. In short, the delete operator is essential whenever you are deleting pointers that were created with new.
Steps for Using the Delete Operator
- Declare a pointer
- Use the new operator to allocate memory for the object of type pointed to by the pointer
- Use the delete operator to deallocate the memory for the object
- Set the pointer to null
Tips and Guidelines
- Use delete on objects that were created using new, and only when you no longer need them. Failure to do so will lead to memory leaks
- The delete operator takes precedence over the assignment operator, so when using delete on a pointer, use the parentheses operator – delete (pointer) – to explicitly denote that you are freeing the memory for the object
- If you are deleting an array of objects, be sure to use the array form of delete: delete[] (pointer)
FAQs
Q1: What is the delete operator?
The delete operator is an operator used for deleting pointers in C++. Its purpose is to free the memory allocated for an object that was previously created using new, and it can be used on both heap objects and member objects.
Q2: When should you use the delete operator?
If you are allocating memory with new and you wish to discard the memory and its content, you should always use the delete operator. Failure to use delete after allocating memory with new will result in a memory leak. In short, the delete operator is essential whenever you are deleting pointers that were created with new.
Q3: What is the syntax for using the delete operator?
The syntax for using the delete operator is as follows: delete pointerName; If you are deleting an array of objects, be sure to use the array form of delete: delete[] (pointerName).
Q4: What happens when you do not use delete after allocating memory with new?
When you do not use delete after allocating memory with new, it will result in a memory leak. This means that the memory will not be freed and the resources allocated for the object will not be released. Eventually, this can lead to a crash or unexpected behavior.
Q5: What is the precedence of the delete operator?
The delete operator takes precedence over the assignment operator, so when using delete on a pointer, use the parentheses operator – delete (pointerName) – to explicitly denote that you are freeing the memory for the object.