How does the element-ui tree component get the selected dom element? the getCurrentNode method in the document does not return dom

how the element-ui tree component gets the selected dom element, the getCurrentNode method in the document does not return dom

tree component, my label name is too long so it overflows. How to add the title attribute, the mouse can display all

on it.
May.15,2021
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-64f5-1bf999e-32195.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1bf999e-32195.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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