Why Do I Get an 'Index Out of Range' Exception When Accessing Collections?

In -depth understanding of the "indexing and Yuejie" abnormalities

Introduction

When processing the set in programming, the use of an invalid index access element may cause the "indexing world" abnormality. This error occurs when the specified index exceeds the boundary of the set permit.

The reason for the error

To understand this error, be sure to master the indexing method of the collection. In most cases, the index of the first element is 0, and the index of the last element is (length -1), where length refers to the number of elements in the set. Try to use index access elements less than 0 or more (length -1) will trigger this abnormality.

For example, consider an array of a statement as var array = new int [6]. The first element is accessed through Array [0], and the last element is accessed through Array [5]. Specifying Index 6 (that is, Array [6]) will cause "indexes" abnormalities because it exceeds the boundary of the set.

Prevent exception

In order to prevent this error, it is necessary to ensure that the indexes used to access elements are within the effective range. In the iterative collection, avoid use of the operator that may cause the index to cross the border. Handling other sets

Other sets, such as lists, follow similar index modes. You can use index access elements from 0 to (count -1). However, it is recommended to use the Foreach mechanism to iterate, because it eliminates the needs of manual management indexing and reduces the risk of errors.

In addition, it should be noted that trying the index element before adding the element to the collection will also trigger the "indexing world" abnormality.

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