即使取消,Javascript回调也会多次触发

时间:2012-10-12 21:22:14

标签: javascript jquery-mobile

我有一个jquery移动对话框,用于确认用户是否要覆盖他们上传的文件。如果用户单击是,则调用要上载的回调函数,如果他们单击否,则关闭对话框并且没有任何反应。

问题在于,如果用户单击否,然后再次单击上载并接受覆盖,则会调用两次回调函数。它正在构建回调,具体取决于它们进入对话状态的时间,我不知道如何处理它。

每次用户点击“上传”时,这都是入口点

CheckOverwriteUpload: function (boxFolderId, fileName) {
            var matchFound = false;
            $.each(BoxManager.Entries, function (index, value) {
                var entry = value;
                if (entry.name == fileName) {
                    matchFound = true;//Found the matching file
                }
            })


            if (matchFound) {
                //Pop the dialog to ask if they want to overwrite the file
                areYouSure("Overwrite File?", "The file " + fileName + " Already exists, would you like to overwrite it?", "Yes", function (result) {
                    if (result == true) {
                        //The client wants to overwrite the file, so we upload it
                        BoxManager.UploadFile(boxFolderId, fileName, true);

                    } else {
                        //The client does not want to overwrite. Close the dialog
                        $("#sure").dialog('close');
                    }
                    //Placed here to close the dialog after the possible upload
                    $("#sure").dialog('close');

                });
            } else {
                //No matches, go ahead and upload
                BoxManager.UploadFile(boxFolderId, fileName, matchFound);
            }

        },

这是对话功能

function areYouSure(text1, text2, button, callback) {

        $("#sure .sure-1").text(text1);
        $("#sure .sure-2").text(text2);
        $("#sure .sure-do").text(button).on("click", function () {
            callback(true);
        });
        $("#sure .close-do").text("No").on("click", function () {
            callback(false);
        });
        $.mobile.changePage("#sure", 'none', false, true);
    }

以防万一需要,这是上传代码。它只是在服务器上调用一个方法

UploadFile: function (boxFolderId, fileName, overWrite) {
            $.mobile.showPageLoadingMsg();
            var etag = "";
            var id = "";
            $.each(BoxManager.Entries, function (index, value) {
                var entry = value;
                if (entry.name == fileName) {
                    etag = entry.etag;//hash of file used to overwrite files on box.com
                    id = entry.id;//unique box id for file. needed to overwrite file
                }
            });
            DocumentVaultService.UploadFileToBox(
                                        "<%=RootFolderGuid %>",
                                        "<%=FolderGuid %>",
                                        "<%=FileGuid %>",
                                        boxFolderId,
                                        fileName,
                                        "<%=IsClientFolder%>",
                                        "<%=AuthToken %>",
                                        overWrite,
                                        etag,
                                        id,
                                        function (result) {
                                            //Success on the upload, refresh the document list and close loading symbol
                                            BoxManager.GetBoxFolderContent(boxFolderId, BoxManager.BreadCrumbList[length - 1].folderName);
                                            $.mobile.hidePageLoadingMsg();
                                        },
                                        function (result) {

                                            $.mobile.hidePageLoadingMsg();
                                            alert("File failed to upload");
                                        });


        }

CheckOverwriteUpload和UploadFile都包含在Boxmanager中,如此

var BoxManager = {
    CheckOverwriteUpload:function(){},
    UploadFile:function(){}
}

如何防止此次呼叫多次?有没有办法在调用对话框之前清除javascript缓存?是否有一个更好的结构,我没有看到回调?

2 个答案:

答案 0 :(得分:0)

每次调用areYouSure()时,它都会再次绑定回调。解决这个问题的一种方法是取消绑定,然后绑定:

$("#sure .close-do").text("No").unbind("click").on("click", function () {
    callback(false);
});

注意unbind("click")。这将删除任何先前的绑定,因此它们不会叠加 另一种方法是将Yes / No按钮绑定放在其他只调用一次的地方(如pageinit)。

答案 1 :(得分:0)

确保不要将同一事件多次绑定到同一个按钮。

此外,在绑定事件时添加命名空间,这样您也不会意外取消绑定其他点击事件。

$('button').off('click.box-manager').on('click.box-manager', function(e){
   ...do something
});

除非你确定没有人会在你的按钮上分配一个事件,否则这是非常的。