How to get length of array in template syntax

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小鲜肉
小鲜肉 2021-02-01 21:24

I am trying to evaluate the below in template syntax which is an array:

FAIL 
{{ cols.length }}

I get the below error.

platfo         


        
2条回答
  •  予麋鹿
    予麋鹿 (楼主)
    2021-02-01 21:27

    Use

    {{ cols?.length }}
    

    Or

    {{ cols.length }}

    If you want to print 0 for empty array, use

    {{ cols?.length || '0' }}
    

    Reason: cols is not initiated when Angular2 load the template. And we want to wait until it's ready to access its members.

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