數組是空的，我想訪問數組arrcolumn []

Question

我想訪問陣列arrcolumn[]我宣佈爲全球array.I正在初始化值陣列arrcolumn[]在OnSuccess1()功能。我想在初始化後OnSuccess()功能使用arrcolumn[]值OnSuccess1（）。 但是arrcolumn[]在OnSuccess()函數中爲空。

var arrname = []; 
var arrmark = []; 
var arrcolumn = []; 
var arr = []; 
var arr1 = []; 
//display function 
function display() { 
    $.ajax({ 
     type: "POST", 
     url: "Default.aspx/fetchStudent", 
     data: '{}', 
     contentType: "application/json;charset=utf-8", 
     dataType: "json", 
     success: OnSuccess, 
     error: OnErrorCall 
    }); 
    $.ajax({ 
     type: "POST", 
     url: "Default.aspx/fetchcolumn", 
     data: '{}', 
     contentType: "application/json;charset=utf-8", 
     dataType: "json", 
     success: OnSuccess1, 
     error: OnErrorCall1 
    }); 

    function OnSuccess1(response) { 

     var objdata1 = (response.d); 
     var pm1 = JSON.parse(objdata1); 
     var len1 = objdata1.length; 
     arr1 = $.map(pm1, function(n, i) { 
      var arr_temp1 = { 
       0: n.name 


      } 
      arrcolumn[i] = n.name; 


      return arr_temp1; 

     }); 



     arrcolumn = jQuery.grep(arrcolumn, function(value) { 
      return value != removeItem; 

     }); 
     arrcolumn = jQuery.grep(arrcolumn, function(value) { 
      return value != removeItem1; 

     }); 

     alert(arrcolumn); 
    } 

    function OnErrorCall1(response) { 
     alert("unable to fecth"); 
    } 

    function OnSuccess(response) { 

     var objdata = (response.d); 
     var pm = JSON.parse(objdata); 
     var len = objdata.length; 
     arr = $.map(pm, function(n, i) { 
      var arr_temp = { 
       0: n.name1, 
       1: n.os, 
       2: n.cn, 
       3: n.pns, 
       4: n.dbms, 
       5: n.se, 
       6: n.c 

      } 
      arrname[i] = n.name1; 
      arrmark[i] = [n.os, n.cn, n.pns, n.dbms, n.se, n.c]; 

      return arr_temp; 

     }); 
     //alert(arrcolumn); 
     alert(arrname); 
     alert(arrmark); 
    } 

    function OnErrorCall(response) { 

     alert("error occured"); 
    } 
} 

Answer 1

你都難保OnSuccess1將OnSuccess後調用。如果您需要兩條信息才能完成工作，則需要等待兩個電話完成。

一個簡單的方法來做到這一點是jQuery的$.when：

$.when(
    $.ajax(/*...*/), // The first call 
    $.ajax(/*...*/) // The second call 
).then(function(result1, result2) { 
    // Both calls are done now. Use `result1` (the result of the 
    // first call) and `result2` (the result of the second) here 
}); 

的通話將並行運行，但最後的處理程序將直到兩個通話完全運行。