TypeError: Cannot read property of null (read 'length'). What does it mean?-PHP Chinese Network Q&A

Article Topic Learning Download Q&A Programming Dictionary Game Recent Updates

简体中文(ZH-CN) English(EN) 繁体中文(ZH-TW) 日本語(JA) 한국어(KO) Melayu(MS) Français(FR) Deutsch(DE)

TypeError: Cannot read property of null (read 'length'). What does it mean?

P粉031492081 2023-11-04 11:52:35

600

I have a problem that I'm trying to solve. Cannot read property of null (read 'conversion'). What does it mean? . I checked the option of integrating mychart.update() from this question https://github.com/chartjs/Chart.js/issues/5149. But when I try to start I get other errors.

TypeError: Cannot read properties of null (reading 'length') at Object.acquireContext (Chart.js?473e:7756:1) at Chart.construct (Chart.js?473e:9324:1) at new Chart (Chart.js?473e:9311:1) at VueComponent.draw (Analytics-test.vue?b2a7:69:1) at VueComponent.loadTrainings (Analytics-test.vue?b2a7:444:1) at async VueComponent.mounted (Analytics-test.vue?b2a7:476:1)

Below you can see the last code I tried to launch.

I also tried this option (using update()):

When I open the string in the debugger:

You can see a reference to this line:

If checking the last reference:

You can see this line:

P粉031492081

reply all (2)

P粉8514014752023-11-05 10:04:31 2 floor

The property length is for an Array and the error states that length cannot be read of null (the important thing is the word "null"), so the problem is that the const or var with that property becomes null for whatever reason. p>