Why Do 'Index Out of Range' Exceptions Occur, and How Can They Be Prevented?

"Index exceeding the range" unusual understanding and solution

"Index exceeding the range" is usually abnormal in the element in the use of numerical index access sets, and the index exceeds the boundary of the set. This error usually occurs when the required index value exceeds the allowable range, and the size of this range from 0 (representing the first element) to the set is reduced by 1 (indicating the last element).

Array index

When the statement has an array with a specified length, the first element is located at Index 0, and the last element is located at the index length -1. This means that an attempt to access the element that is less than 0 or greater than Length -1 will cause abnormalities.

The indexes of other sets

Similar to the array, the list and other sets follow the same index agreement. The element can access the count -1 from the index 0. Similarly, access to elements outside of this range will trigger abnormalities. Prevent indexes from errors

In order to avoid errors that exceed the scope of the index, it is necessary to ensure that the selected attraction is maintained in the boundary of the collection. This requires comparison with the size or count of the collection before accessing the element. In addition, the use of iterators (for example, Foreach cycle) is a convenient alternative to manual indexing, while avoiding the risk of index errors.

New elements and index errors

Please note that the element that has not been added to the collection in the set will also cause an error in the index exceeding the range. To prevent this, I only try to access the elements that have been added to the corresponding collection.

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