Usage of const in vue

const in Vue.js is used to declare constants, that is, variables that cannot be reassigned at runtime. It is mainly used to declare values ​​that will not change to prevent accidental overwriting of important variables.

Usage of const in Vue.js

const in Vue.js The keyword is used to declare constants, that is, variables that cannot be reassigned at runtime.

Usage:

const Mainly used in the following scenarios:

• Declare values ​​that will not change, such as : API endpoint URL, global configuration items
• Prevent accidental overwriting of important variables

Syntax:

<code class="javascript">const myConstant = 'Hello World';</code>

Note:

• Constant values ​​must be initialized when declared.
• Once declared, constants cannot be reassigned. Any attempt to reassign will result in an error. For example:

<code class="javascript">const myConstant = 'Hello World';
myConstant = 'Goodbye World'; // 错误</code>

Advantages:

• Security: const Prevents accidental overwriting of key variables to improve code stability.
• Readability: const Clearly indicates that the variable value is immutable, improving code readability.

Limitations:

• Limited flexibility: const The value of the variable cannot be used at runtime changes from time to time, this may be restricted in some cases.

Best Practice:

• Use const only when really needed.
• Avoid using const to declare frequently updated values.
• Consider using let or var to declare mutable variables.

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