[译]MVC网站教程（四）：MVC4网站中集成jqGrid表格插件（系列完结）

public

IQueryable<T>LoadGridData<T>(IQueryable<T>dataSource,

out

int

count)

{

var

query = dataSource;

//

// Sorting and Paging by using the current grid settings.

//

query = query.OrderBy<T>(

this

.SortColumn,

this

.SortOrder);

count = query.Count();

//

if

(

this

.PageIndex <1)

this

.PageIndex =1;

//

var

data = query.Skip((

this

.PageIndex - 1) *

this

.PageSize).Take(

this

.PageSize);

return

data;

}

public

object

BindModel(ControllerContext controllerContext,ModelBindingContext bindingContext)

{

try

{

var

request = controllerContext.HttpContext.Request;

return

new

GridSettings

{

PageIndex =

int

.Parse(request[

"page"

] ??

"1"

),

PageSize =

int

.Parse(request[

"rows"

] ??

"20"

),

SortColumn = request[

"sidx"

] ??

""

,

SortOrder = request[

"sord"

] ??

"asc"

,

};

}

catch

{

//

// For unexpected errors use the default settings!

//

return

null

;

}

}

public

static

IQueryable<T>OrderBy<T>(

this

IQueryable<T>query,

string

sortColumn,

string

direction)

{

string

methodName =

string

.Format(

"OrderBy{0}"

,

direction.ToLower() ==

"asc"

?

""

:

"descending"

);

ParameterExpression parameter = Expression.Parameter(query.ElementType,

"p"

);

MemberExpression memberAccess =

null

;

//

foreach

(

var

property

in

sortColumn.Split(

'.'

))

{

memberAccess = MemberExpression.Property(memberAccess ??(parameter

as

Expression),property);

}

//

LambdaExpression orderByLambda = Expression.Lambda(memberAccess,parameter);

MethodCallExpression result =Expression.Call(

typeof

(Queryable),

methodName,

new

[] { query.ElementType,memberAccess.Type },

query.Expression,

Expression.Quote(orderByLambda));

//

// For the sortColumn=='User.Username' and  direction=="desc" ==>

//   "OrderByDescending(p =>p.User.Username)" expression

// will be appended to the input query!

//

return

query.Provider.CreateQuery<T>(result);

}

public

static

IQueryable<VisitorLog>SearchLogByDates(MvcBasicSiteEntities dataContext,DateTime searchStartDate,DateTime searchEndDate)

{

if

(searchStartDate.Date == DateTime.MinValue && searchEndDate.Date == DateTime.MinValue)

{

return

dataContext.VisitorLogs.AsQueryable();

}

else

if

(searchStartDate.Date == DateTime.MinValue)

{

var

searchResults = dataContext.VisitorLogs.Where(c =>

EntityFunctions.TruncateTime(c.StartDate) <= EntityFunctions.TruncateTime(searchEndDate));

//

return

searchResults.AsQueryable();

}

else

if

(searchEndDate.Date == DateTime.MinValue)

{

var

searchResults = dataContext.VisitorLogs.Where(c =>

EntityFunctions.TruncateTime(c.StartDate) >= EntityFunctions.TruncateTime(searchStartDate));

//

return

searchResults.AsQueryable();

}

else

{

var

searchResults = dataContext.VisitorLogs.Where(c =>

EntityFunctions.TruncateTime(c.StartDate) >= EntityFunctions.TruncateTime(searchStartDate) &&

EntityFunctions.TruncateTime(c.StartDate) <= EntityFunctions.TruncateTime(searchEndDate));

//

return

searchResults.AsQueryable();

}

}

<table id=

"_visitorLogGrid"

cellpadding=

"0"

cellspacing=

"0"

>

</table>

<div id=

"_visitorLogPager"

style=

"text-align:center;"

>

</div>

function

showGrid() {

$(

'#_visitorLogGrid'

).jqGrid({

caption:paramFromView.Caption,

colNames:[

'ID'

,paramFromView.VisitorName,paramFromView.StartDate,

paramFromView.EndDate,paramFromView.WasTimeOut,paramFromView.Actions],

colModel:[

{ name:

'ID'

,width:1,hidden:

true

,key:

true

},

{ name:

'VisitorName'

,index:

'User.Username'

,width:300 },

{ name:

'StartDate'

,index:

'StartDate'

,width:150 },

{ name:

'EndDate'

,index:

'EndDate'

,width:150 },

{ name:

'WasTimeOut'

,index:

'WasTimeOut'

,width:120,

formatter:

"checkbox"

,align:

"center"

},

{ name:

'Action'

,index:

'ID'

,width:70,align:

"center"

}

],

hidegrid:

false

,

pager:jQuery(

'#_visitorLogPager'

),

sortname:

'ID'

,

rowNum:paramFromView.PageSize,

rowList:[10,20,50,100],

sortorder:

"desc"

,

width:paramFromView.Width,

height:paramFromView.Height,

datatype:

'json'

,

caption:paramFromView.Caption,

viewrecords:

true

,

mtype:

'GET'

,

jsonReader:{

root:

"rows"

,

page:

"page"

,

total:

"total"

,

records:

"records"

,

repeatitems:

false

,

userdata:

"userdata"

},

url:paramFromView.Url

}).navGrid(

'#_visitorLogPager'

,{ view:

false

,del:

false

,add:

false

,edit:

false

,search:

false

},

{ width:400 },

// default settings for edit

{},

// default settings for add

{},

// delete instead that del:false we need this

{},

// search options

{}

/* view parameters*/

).navButtonAdd(

'#_visitorLogPager'

,{

caption:paramFromView.DeleteAllCaption,buttonimg:

""

,onClickButton:

function

() {

if

(confirm(paramFromView.DeleteAllConfirmationMessage)) {

document.location = paramFromView.ClearGridUrl;

}

else

{

$(

'#_visitorLogGrid'

).resetSelection();

}

},position:

"last"

});

};

$(document).ready(

function

() {

showGrid();

});

@

using

MvcBasicSite.Models.Grid;

@{

ViewBag.Title = Resources.Resource.VisitorLogIndexTitle;

Layout =

"~/Views/Shared/_AdminLayout.cshtml"

;

//

int

pageSize = 20;

if

(Session[

"VisitorLogGridSettings"

] !=

null

)

{

//

// Get from cache the last page zise selected by the user.

//

GridSettings grid =

new

GridSettings((

string

)Session[

"VisitorLogGridSettings"

]);

pageSize = grid.PageSize;

}

//

// Restore the last search params from cache.

//

string

startDate = (Session[

"StartDate"

] ==

null

?

string

.Empty

:((DateTime)Session[

"StartDate"

]).ToShortDateString());

string

endDate = (Session[

"EndDate"

] ==

null

?

string

.Empty

:((DateTime)Session[

"EndDate"

]).ToShortDateString());

}

<table>

<tr>

<td style=

"text-align:right;margin-top:0px;"

>

@

using

(Ajax.BeginForm(

"Search"

,

"VisitorLog"

,

new

AjaxOptions

{

HttpMethod =

"GET"

,

InsertionMode = InsertionMode.Replace,

UpdateTargetId =

"jqGrid"

,

OnSuccess =

"showGrid()"

}))

{

<table>

<tr>

<td>

<label>@Resources.Resource.VisitorLogIndexFrom</label>

<input type=

"text"

id=

"from"

name=

"from"

data-datepicker=

"true"

value=

"@startDate"

/>

</td>

<td>

<label>@Resources.Resource.VisitorLogIndexTo</label>

<input type=

"text"

id=

"to"

name=

"to"

data-datepicker=

"true"

value=

"@endDate"

/>

</td>

<td style=

"text-align:right;margin-top:0px;"

>

<input type=

"submit"

name=

"_search"

value=

"@Resources.Resource.VisitorLogApplyFilter"

class

=

"searchButton"

/>

</td>

</tr>

</table>

}

</td>

</tr>

</table>

<div id=

"jqGrid"

>

@Html.Partial(

"_VisitorLogGrid"

)

</div>

<script type=

"text/javascript"

>

var

paramFromView = {

DeleteAllCaption:

'@Resources.Resource.VisitorLogDeleteAllCaption'

,

ClearGridUrl:

'@Url.Content("~/VisitorLog/ClearGridData")'

,

DeleteAllConfirmationMessage:

'@Resources.Resource.VisitorLogDeleteAllDataConfirmation'

,

Url:

'@Url.Content("~/VisitorLog/GetData")'

,

Width:790,

Height:464,

Caption:

'@Resources.Resource.VisitorLogIndexTitle'

,

VisitorName:

'@Resources.Resource.VisitorLogIndexVisitorName'

,

StartDate:

'@Resources.Resource.VisitorLogIndexStartDate'

,

EndDate:

'@Resources.Resource.VisitorLogIndexEndDate'

,

WasTimeOut:

'@Resources.Resource.VisitorLogIndexWasTimeOut'

,

Actions:

'@Resources.Resource.VisitorLogIndexActions'

,

PageSize:@pageSize

}

</script>

@section scripts

{

@Content.Script(

"VisitorLogGrid.js"

,Url)

}

public

JsonResult GetData(GridSettings grid)

{

if

(_fromIndex && Session[

"VisitorLogGridSettings"

] !=

null

)

{

//

// Get grid settings from cache!

//

grid =

new

GridSettings((str ing)Session[

"VisitorLogGridSettings"

]);

}

//

_fromIndex =

false

;

// Must be set on false here!

//

// Load the data from the database for the current grid settings.

//

DateTime searchStartDate = (Session[

"StartDate"

] ==

null

?

DateTime.MinValue :(DateTime)Session[

"StartDate"

]);

DateTime searchEndDate = (Session[

"EndDate"

] ==

null

?

DateTime.MinValue :(DateTime)Session[

"EndDate"

]);

int

count;

var

query = grid.LoadGridData<VisitorLog>(

VisitorLog.SearchLogByDates(_db,searchStartDate,searchEndDate),

out

count);

var

data = query.ToArray();

//

// Convert the results in JSON jqGrid format.

//

string

gridSettingsString =grid.ToString();

// Used to preserve grid settings!

Session[

"VisitorLogGridSettings"

] = gridSettingsString;

gridSettingsString =

null

;

var

result =

new

{

total = (

int

)Math.Ceiling((

double

)count / grid.PageSize),

page = grid.PageIndex,

records = count,

rows = (

from

host

in

data

select

new

{

ID = host.ID,

VisitorName = GetVisitorNameForBinding(host),

StartDate = host.StartDate.ToString(),

EndDate = host.EndDate.ToString(),

WasTimeOut = (host.WasTimeOut ??

false

),

Action =

string

.Format(

"{0}"

,

RenderHelpers.ImageButton(

this

,

Resources.Resource.DeleteTip,

"~/Content/Images/Delete.gif"

,

"Delete"

,

new

{ id = host.ID },

new

{ style =

"border:0px;"

}))

}).ToArray()

};

//

// Convert to JsonResult before to return.

//

return

Json(result,JsonRequestBehavior.AllowGet);

}

public

PartialViewResult Search()

{

string

startDate = Request[

"from"

];

string

endDate = Request[

"to"

];

//

// Cache the start and end dates into the session to be used by later one in the view.

//

Session[

"StartDate"

] = (startDate.Length <1 ?

null

:

(

object

)DateTime.Parse(startDate,Thread.CurrentThread.CurrentCulture));

Session[

"EndDate"

] = (endDate.Length <1 ?

null

:

(

object

)DateTime.Parse(endDate,Thread.CurrentThread.CurrentCulture));

//

return

PartialView(

"_VisitorLogGrid"

);

}

public

ActionResult ClearGridData()

{

DateTime searchStartDate = (Session[

"StartDate"

] ==

null

?

DateTime.MinValue :(DateTime)Session[

"StartDate"

]);

DateTime searchEndDate = (Session[

"EndDate"

] ==

null

?

DateTime.MinValue :(DateTime)Session[

"EndDate"

]);

VisitorLog.DeleteLogByDates(_db,searchStartDate,searchEndDate);

//

return

RedirectToAction(

"Index"

);

}