For a C# List, how do I reorder a column when one record's value changes? -

i have kendo grid user can change order of rows moving rows , down. adjust order field incrementing or decrementting one. need reorder rest of items in grid. pass data controller , trying reorder list. feel i'm close, can't quite right. can me figure out how this?

example:

start grid

test | order    | 1   b  | 2   c  | 3   d  | 4 

the user clicks on b row , arrow grid looks this:

test | order   b  | 1    | 1   c  | 3   d  | 4 

this part working fine don't think code necessary. here's need help. controller , have list this:

[0] test: b, order: 1 [1] test: a, order: 1 [2] test: c, order: 3 [3] test: d, order: 4 

there 2 records order equals 1. how reorder list (so can save new order database?

what want list looks this:

[0] test: b, order: 1 [1] test: a, order: 2 [2] test: c, order: 3 [3] test: d, order: 4 

i came solution, recursive part isn't working right. list returned blank. can find what's wrong?

    [httppost]     public actionresult updatecomments([datasourcerequest] datasourcerequest request, modelcomment model)     {         list<modelcomment> comments = new list<modelcomment>();          comments.add(model);          list<modelcomment> othercomments = data.getcommentsbyanalysisid(model.analysisid);          list<modelcomment> changedcomments = changeduplicateorders(othercomments, model.commentsselectedid, model.order);          return json(comments.todatasourceresult(request));     }      private list<modelcomment> changeduplicateorders(list<modelcomment> comments, int id, int order)     {         list<modelcomment> changedcomments = new list<modelcomment>();          foreach (modelcomment comment in comments)         {             if (comment.commentsselectedid != id)             {                 modelcomment changedcomment = comment;                  if (comment.order == order)                 {                     changedcomment.order = order + 1;                     changedcomments.add(changedcomment);                 }                  list<modelcomment> remainingcomments = new list<modelcomment>();                 remainingcomments = comments;                 remainingcomments.remove(changedcomment);                  list<modelcomment> processedcomments = changeduplicateorders(remainingcomments, changedcomment.commentsselectedid, changedcomment.order);                 changedcomments = (changedcomments.concat(processedcomments)).tolist();             }         }          return changedcomments;     } 

edit: here's view can see i'm doing on client side:

@using (html.beginform("labapprovals_history", "home")) { <div class="breadcrumb">     @html.raw(@clsutility.getcurrentcrumb("lab approvals comments")) </div> if (@viewbag.message != null && @viewbag.message != "") {     <div id="diverrormessage" style="color: #1a78c2;">         <br />         @html.raw(@viewbag.message)     </div>     <br />     <div style="clear: both">         <br />     </div> } <br /> <div style="text-align: center; padding-left: 10px;">     <div id="grid"></div>     @(html.kendo().grid<dalubebarcode.models.modelcomment>().name("gridcomments")                             .datasource(datasource => datasource                                 .ajax()                                 .read(read => read.action("readcomments", "home", new { analysisid = model.analysisid }))                                 .update(update => update.action("updatecomments", "home"))                                 .model(model => model.id(p => p.commentsselectedid))                             )                             .toolbar(toolbar => toolbar.save())                             .columns(columns =>                             {                                 columns.bound(m => m.commentsselectedid).visible(false);                                 columns.bound(m => m.commenttext).title("comment").width("500px");                                 columns.bound(m => m.order)                                     .clienttemplate("<input type='button' class='k-button' onclick=up(\'#=uid#\') value='up' />").title("");                                 columns.bound(m => m.order)                                     .clienttemplate("<input type='button' class='k-button' onclick=down(\'#=uid#\') value='down' />").title("");                                 columns.bound(m => m.order).title("order").width("50px");                             })                         .sortable()                         .htmlattributes(new { style = "height:600px;" })                         .resizable(resize => resize.columns(true))                         .editable(editable => editable.mode(grideditmode.incell)) ) </div>  }  <script> function up(uid) {     var grid = $("#gridcomments").data("kendogrid");     var dataitem = grid.datasource.getbyuid(uid);     dataitem.order = dataitem.order - 1;      var index = grid.datasource.indexof(dataitem);     var newindex = math.max(0, index - 1);      if (newindex != index) {         grid.datasource.remove(dataitem);         grid.datasource.insert(newindex, dataitem);     }      var datasource = $("#gridcomments").data("kendogrid").datasource;     datasource.data()[newindex].dirty = true;     datasource.sync();      return false; }  function down(uid) {     var grid = $("#gridcomments").data("kendogrid");     var dataitem = grid.datasource.getbyuid(uid);     dataitem.order = dataitem.order + 1;      var index = grid.datasource.indexof(dataitem);     var newindex = math.min(grid.datasource.total() - 1, index + 1);      if (newindex != index) {         grid.datasource.remove(dataitem);         grid.datasource.insert(newindex, dataitem);     }      var datasource = $("#gridcomments").data("kendogrid").datasource;     datasource.data()[newindex].dirty = true;     datasource.sync();      return false; } 

something work, dont have time check syntax, watch out capitalization , such:

 private void reorder (mylist, oldindex, newindex) {      modelcomment itemtomove = mylist.first(x=>x.order==oldindex);      modelcomment insertpoint = mylist.first(x=>x.order==newindex);      mylist.remove(itemtomove);      if (newindex < oldindex) {          mylist.select(x=>x.order>=newindex && x.order<oldindex).foreach(x=>x.order++);      } else {          mylist.select(x=>x.order<=newindex && x.order>oldindex).foreach(x=>x.order--);      }      itemtomove.order = newindex;      mylist.insert(mylist.indexof(insertpoint), itemtomove);  }