Filter data in list grid based dropdown selection

I Have created doc and added one drop-down field with data bank names.
when i select bank name from drop-down i want employee data in list grid based on selected bank.
(whole employee list belongs to selected bank)

This will require you to write a custom script

Thanks @umair
Its working for single field only not for child grid

I am looking for fetch data in child grid based on dropdown selection

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I want to list of employee data in above grid based on Bank name Drop down list
e.g : Select Bank name is : HDFC

in List grid i want whole employee list whose bank name(In Employee) is HDFC

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any one can help me for do this??

if Leave Type == “Earned Leaved” then in it’s linked field for clubbed Leave Type should I show only Sick Leave and paternity Leave

can someone help me