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Below I will share with you an article on how to use index to add a class to the first item in Vuejs in v-for. It has a good reference value and I hope it will be helpful to everyone.
(1) In v-for, use index to add class to the first item
View the code piece on CODE derived to My code piece
index comes from v-for, i represents the element of the traversed array, and index represents the index.
Since index starts from 0, if you want to specify that the first item has the active class, then use v-bind:class="{'active':!index}"
One item is originally false (0), and the second item and the subsequent item are true (>0). Their values are reversed through the logical NOT operator.
Therefore, the first item has the active class, but the following items do not.
If there is a class other than the first item, it can also be achieved by not adding the logical NOT operator.
Similarly, you can use an expression such as index==2 to let the third item obtain this class.
Note, My version is Vuejs2.0, so it seems that it cannot be replaced with $index.
The above is what I compiled for everyone. I hope it will be helpful to everyone in the future.
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