jquery Plug-in Extension instance "Add callback function" _jquery

This example describes the method of the jquery plug-in extension. Share to everyone for your reference, specific as follows:

<script language= "javascript" type= "Text/javascript" >
function dosomething (callback) {
  //... 
  Call the callback
  callback (' Stuff ', ' goes ', ' here ');//Give callback assign value, callback is a function variable
} functions
foo1 (A, B, c) {
  //I ' m The callback
  alert (A + "" + B + "" + C);
}
DoSomething (FOO1);  The FOO1 function will use the data in the callback function stuff goes here
var foo2 = function (a,b,c) {
  //I ' m The callback
  alert (A + "" + B + "" + C);
}
DoSomething (FOO2); The FOO2 function uses the data in the callback function to stuff goes here
dosomething (function (a,b,c) {
  alert (A + "" + B + "" + C); function functions will use the data in the callback function stuff goes here
});
</script>

Callback This parameter must be a function to be valid. Can play a role in callback.

<script language= "javascript" type= "Text/javascript" >
function dosomething (callback) {
  //... 
  Call the callback
  if (typeof callback = = ' function ') {
    callback (' Stuff ', ' goes ', ' here ');/= assign value to callback Callback is a function variable
  }else{
    alert (' jb51.net ');
  }
function Foo1 (A, B, c) {
  //I ' m The callback
  alert (A + "" + B + "" + C);
}
DoSomething (FOO1);  The FOO1 function will use the data in the callback function stuff goes here
var foo2 = function (a,b,c) {
  //I ' m The callback
  alert (A + "" + B + "" + C);
}
DoSomething (FOO2); The FOO2 function uses the data in the callback function to stuff goes here
dosomething (function (a,b,c) {
  alert (A + "" + B + "" + C); function functions will use the data in the callback function stuff goes here
});
var Foo3 = ' a ';
DoSomething (FOO3);
</script>

Foo3 is not a function when the pop-up jb51.net

jquery instances

Original function

$.fn.cityselect=function (Settings)

Add callback

$.fn.cityselect=function (settings, Changehandle)//Add callback function Changehandle

Assign a value to a callback function

Option variable Assignment event
var selectchange = function (areatype) { 
  if (typeof changehandle = = ' function ') {//Judge whether callback is a function C3/>var prov_id = prov_obj.get (0). SelectedIndex;
    var city_id = city_obj.get (0). SelectedIndex;
    var dist_id = dist_obj.get (0). SelectedIndex;
    if (!settings.required) {
      prov_id--;
      city_id--;
      dist_id--;
    };
    if (dist_id<0) {
      var data = {
        PROV:CITY_JSON.CITYLIST[PROV_ID].P,
        city:city_json.citylist[prov_id ].C[CITY_ID].N,
        dist:null
      };
    else{
      var data = {
        PROV:CITY_JSON.CITYLIST[PROV_ID].P,
        city:city_json.citylist[prov_id].c[city_id] . N,
        Dist:city_json.citylist[prov_id].c[city_id].a[dist_id].s
      };
    Changehandle (data, areatype); Returns two processed data
  }
};

Get data from the provinces and counties and trigger the Change event type Areatype

Event
prov_obj.bind ("Change", function () {
    citystart ()) When the province is selected;
    Selectchange (' Prov '); Return Data
});
Event
city_obj.bind ("Change", function () {
    diststart ()) when the city level is selected;
    Selectchange (' City '); Return Data
});
Event
dist_obj.bind ("Change", function () {
    selectchange (' dist ');//Return Data}) occurs when the zone level is selected
;

Executing in individual events

Front-End use

$ ("#s_city"). Cityselect ({
  prov: "Jiangsu Province", City
  : "Suqian",
  Dist: "Sucheng District",
  nodata: "None"
},
function (data, type) {
  selectagent (data.city, data.dist);
});

Use the callback back to the data, used in the Selectagent function

function Selectagent (city,district) {
    $.ajax ({
      type: "POST",
      URL: "{sh::u (' Index/ajax '), array (' Todo ' = > ' getagent ')} ",
      data:" city= "+city+" &district= "+district,
      success:function (JSON) {
        JSON = Json.parse (JSON);
        Opt_str = "<option value= ' >-Please select-</option>"
        if (Json.status = 1) {
          $.each ( Index,con) {
            opt_str = "<option value=" +con.id+ ">" +con.name+ "Tel:" +con.tel+ "</option>"
          })
        }
        $ (' #agent_id '). HTML (OPT_STR);
      }
    );

Go to Ajax to get the appropriate agent data.

Retrofit plugin complete.

For more information on jquery-related content readers can view the site topics: "jquery common Plug-ins and Usage summary", "JQuery Extended Skills Summary", "jquery switching effects and Skills summary", "jquery traversal algorithm and Skills summary", " jquery Common Classic Effects Summary "jquery animation and special effects usage Summary" and "jquery Selector usage Summary"

I hope this article will help you with the jquery program design.