Issue of using filters in vue with this undefined

This is undefined using filters filters

Filters in vue prefer to convert text data, and cannot rely on this context. If you need to use this context, we should use computed to calculate attributes or a method method

Usage of vue filter filter

{undefined{ args | filterFun }} | is the pipe character The usage is as follows

{{ time | formatDate }}

In the filter

filters: {
        formatDate: value => {
           let date = new Date(value)
           let y = ()
           let MM = () + 1
           MM = MM < 10 ? "0" + MM : MM
           let d = ()
           d = d < 10 ? "0" + d : d
           let h = ()
           h = h < 10 ? "0" + h : h
           let m = ()
           m = m < 10 ? "0" + m : m
           let s = ()
           s = s < 10 ? "0" + s : s
           return y + "-" + MM + "-" + d + " " + h + ":" + m + ":" + s
        }
    }

time is equivalent to the value you want to filter. The parameter passed to formatDate

You can also use multiple parameters {undefined{ time | formatDate("Hey Ha") }}

In this filter

//time passed to value    "Hey Ha" passed to arg1formatDate: (value,arg1) => {
    ......
}

The above is personal experience. I hope you can give you a reference and I hope you can support me more.