Sort Grid Columns of mixed type in EXTJS Grid

I want to sort the extjs columns, I have the column type as float and from the server side i am getting values which can contain "-" value , now what happens the grid is displaying m开发者_Go百科e the NaN value instead of - and the sort is not working anymore.

My requirement is to create a custom sort which can sort first based on number and then sort based on string.

Thanks to suggest as renderer also not works for me.

My Json String is:

{metaData:{"totalProperty":"total", "root":"records","fields":[{"header":"Part Number##false","name":"XJE010^VT-007!0","type":"string"},{"header":"Marketing Status##false","name":"STP716^VT-007!0","type":"string"},{"header":"Package##false","name":"XJE016^VT-007!0","type":"string"},{"header":"Automotive Grade##false","name":"STP472^VT-007!0","type":"string"},{"header":"VDSS##false","name":"XJG810^VT-007!0","type":"float"},{"header":"Drain Current (Dc)(I_D) % (A)##false","name":"XJG273^VT-006!0","type":"float"},{"header":"RDS(on) (@VGS=10V) % (Ω)##false","name":"XJG640^VT-006!3","type":"float"},{"header":"Features##false","name":"GNP023^VT-007!0","type":"string"},{"header":"RDS(on) (@4.5 or 5V) % (Ω)##false","name":"XJG640^VT-006!6","type":"float"},{"header":"RDS(on) (@2.7V) % (Ω)##false","name":"XJG640^VT-006!7","type":"float"},{"header":"RDS(on) (@1.8V) % (Ω)##false","name":"XJG640^VT-006!8","type":"float"},{"header":"Free Samples##false","name":"STP0881^VT-007!0","type":"string"},{"header":"Total Gate Charge(Qg) typ ()##true","name":"STP049^VT-002!0","type":"float"},{"header":"Total Power Dissipation(PD) % (W)##true","name":"XJG820^VT-006!0","type":"float"}]},"success":"true", "total":13,"records":[{"XJE010^VT-007!0":"STB80PF55$$/cn/analog/product/67164.jsp","STP716^VT-007!0":"Active","XJE016^VT-007!0":"D2PAK","STP472^VT-007!0":"_","XJG810^VT-007!0":"-55","XJG273^VT-006!0":"80","XJG640^VT-006!3":".018","GNP023^VT-007!0":"-","XJG640^VT-006!6":"-","XJG640^VT-006!7":"-","XJG640^VT-006!8":"-","STP0881^VT-007!0":"No","STP049^VT-002!0":"190","XJG820^VT-006!0":"300"},{"XJE010^VT-007!0":"STD10PF06$$/cn/analog/product/64543.jsp","STP716^VT-007!0":"Active","XJE016^VT-007!0":"IPAK TO-251 TO 252 DPAK","STP472^VT-007!0":"_","XJG810^VT-007!0":"-60","XJG273^VT-006!0":"-10","XJG640^VT-006!3":".2","GNP023^VT-007!0":"-","XJG640^VT-006!6":"-","XJG640^VT-006!7":"-","XJG640^VT-006!8":"-","STP0881^VT-007!0":"No

...

Create a custom Store based on/extended from your choice of Store and override the sortData method to create and use a custom sort function as appropriate (see createSortFunction in same object for reference http://dev.sencha.com/deploy/dev/docs/source/Store.html#method-Ext.data.Store-sort).

Alternatively you can override the sorting parameter before loading the grid store.

This link https://dotnetlooker.wordpress.com/2017/11/26/extjs-grid-custom-sort-of-mixed-type-with-hyphen-values/ should help you. It provides a working example and a in-depth explanation.