How to write the value passed by the vue typescrip child component to the parent component

how to write the value passed by the vue typescrip child component to the parent component.
can"t trigger with @ emit

Mar.22,2021

component code


export default class HelloWorld{
    emitValue = {value:1} // here
    @Emit('onHelloClick')
    componentHandleClick(val: any) {
        console.log('emit step 1')
        this.emitValue.value += 1 // here
        console.log('emit step 2')
    }
}
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b3ad64-2c240.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b3ad64-2c240.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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