Question

这段代码有什么问题？我正在使用jQuery。

function setPreviewUrl() { 
     $post_title = $("#post_title").val(); 
     $post_content = $("#post_content").val(); 
     $.get('ajax/base64encode.php?name='+post_title, function(data1) { 
      var $postTitle = null; 
      $postTitle = data1; 
     }); 
     $.get('ajax/base64encode.php?name='+post_content, function(data2) { 
      var $postCont = null; 
      $postCont = data2; 
     }); 
     var $urlExten = null; 
     $urlExten = '?post_title='+postTitle+'&post_cont='+postCont; 
     $("a[href*='#change']").attr('href', '<?php echo $site_url; ?>admin/ajax/preview.php'+urlExten); 
     $("#preview_frame").prop("href", '<?php echo $site_url; ?>admin/ajax/preview.php'+urlExten); 
    } 

Answer 1

好像你搞乱了异步代码：

function setPreviewUrl() { 
     var $post_title = null; 
     $post_title = $("#post_title").val(); 
     var $post_content = null; 
     $post_content = $("#post_content").val(); 
     $.get('ajax/base64encode.php?name='+post_title, function(data1) { 
      var $postTitle = null; 
      $postTitle = data1; 
     }); 
     $.get('ajax/base64encode.php?name='+post_content, function(data2) { 
      var $postCont = null; 
      $postCont = data2; 
     }); 
     // Those functions above will execute when the get is done, in the 
     // meantime the code below is executed, so the variables have not been 
     // set yet. 
     // Also, the variables are only declared inside the get function so they 
     // are not accessible due to their scope. 
     var $urlExten = null; 
     $urlExten = '?post_title='+postTitle+'&post_cont='+postCont; 
     $("a[href*='#change']").attr('href', '<?php echo $site_url; ?>admin/ajax/preview.php'+urlExten); 
     $("#preview_frame").prop("href", '<?php echo $site_url; ?>admin/ajax/preview.php'+urlExten); 
    }