ASP.NET Core Treeview checkAll() function is very slow

Question

When using the checkAll() function with 100+ Ids as Parameter its very slow to the point that it will freeze the browser.

When Setting the Tree to loadonDemand = false the function will not work at all.

Keerthana Rajendran · Accepted Answer

Hi Florian, 
 
We have validated your reported problem. We have prepared a Core TreeView sample with 100+ to 1000 node items and ensured checkAll (with loadonDemand false case too). However, the checkAll functionality was performed in a feasible amount of time and we couldn’t replicate the time delay issue in our end. Your reported issue with loadonDemad may occur due to the Id type in your datasource. By default, Id argument must be in string type. 
 
Please find the sample from the below link, 
 
https://www.syncfusion.com/downloads/support/forum/161719/ze/Core_TreeView-345215413 
 
If the issue still persists, please share the below details 
 

Number of items loaded as DataSource in your application?
Video footage of the reported problem.
If possible, modify the above sample to replicate the issue to serve you better. 
 
Please, let us know if you need any further assistance. 
 
Regards, 
Keerthana.