SvelteKit 响应式助手

<!-- viewportsettingscatchr.svelte -->
<script lang="ts">
    let innerwidth: number = 1600
    let innerheight: number = 1200
</script>

<svelte:window bind:innerwidth vind:nnerheight />

$: viewportsettingsstore.register ({ innerwidth, innerheight })

import { writable} from 'svelte/store'
const { subscribe, update  } = writable ({
    innerwidth: 1600, 
    innerheight: 1200,
    ratio: 16/12, 
    orientation: 'landscape',   
    wide: false
})

function register ({ innerwidth, innerheight }) {
    const ratio = innerwidth / innerheight
    const orientation = ratio >= 1 ? 'landscape' : 'portrait'
    const wide = (ratio > 2) || (ratio < 0.5)

    update ((state) => {
        return {
            innerwidth, 
            innerheight,
            orientation,
            ratio,
            wide
        }
    })
}

export const viewportsettingsstore = {
    subscribe, register 
}

<div class:wide={ $ViewportSettingsStore.orientation = === 'landscape' } />