jQuery的 - 生成的元素的新屬性不會保存

Question

當我創建元素，這是動態生成新的屬性，它不保存：

$("#div-main").on("mouseover", ".generated", function(e) 
{ 
    console.log("hover"); 
    console.log($(this).attr("title")) // always undefined 

    if (typeof $(this).attr("title") === typeof undefined) 
    { 
     $.get("<URL with PHP>", function(data) 
     { 
      if (data != "") 
      { 
      $(this).attr("title", data); 
      console.log($(this).attr("title")); // data shows 
      } 
      else 
      { 
      $(this).attr("title", "no data"); 
      console.log($(this).attr("title")); // "no data" shows 
      } 
     }); 
    } 
    else 
    { 
     console.log("'title' attribute already set"); 
    } 
}); 

#div-main不會產生。帶有類.generated的元素是動態生成的元素。

Answer 1

這是因爲this是AJAX回調內部不同

$("#div-main").on("mouseover", ".generated", function(e) 
{ 
    console.log("hover"); 
    console.log($(this).attr("title")) // always undefined 

    if (typeof $(this).attr("title") === typeof undefined) 
    { 
    var that = this; //CONTEXT 
    $.get("<URL with PHP>", function(data) 
    { 
     if (data != "") 
     { 
     $(that).attr("title", data); 
     console.log($(that).attr("title")); // data shows 
     } 
     else { 
      $(that).attr("title", "no data"); 
      console.log($(that).attr("title")); // "no data" shows 
     } 
     }); 
    } else { 
     console.log("'title' attribute already set"); 
    } 
});