Javascript jQuery自动完成变量范围
我对这个函数中变量的范围有问题。基本上,当用户关注将有jQuery下拉列表的textbox时,我希望将旧值保存在textbox中(如果存在),以便在需要时恢复它。我还尝试在函数外部声明Javascript jQuery自动完成变量范围,javascript,jquery,variables,scope,Javascript,Jquery,Variables,Scope,我对这个函数中变量的范围有问题。基本上,当用户关注将有jQuery下拉列表的textbox时,我希望将旧值保存在textbox中(如果存在),以便在需要时恢复它。我还尝试在函数外部声明previous,并将其作为窗口。previous但没有成功。问题是,当我从下拉列表函数中使用previous变量时,我总是将其返回为未定义的 // Delete option allows a user to delete the value directly from the textbox associate
previous
,并将其作为窗口。previous
但没有成功。问题是,当我从下拉列表函数中使用previous
变量时,我总是将其返回为未定义的
// Delete option allows a user to delete the value directly from the textbox associated with the dropdown.
// Otherwise he will be warned and always forced to make a choice.
// With value will add an extra value to a textbox that has _val apended to the current id
// Create new, if set will open a new confirmation to add the item to the dropdown list
function acomplete(element, source, deleteoption, withvalue, createnew, createtable, createcolumn, retid) {
var previous;
// Add arrow as this is a dropdown
$(element).addClass("dropdown");
$(element).autocomplete({
source: source,
minLength: 0,
global: false,
select: function (event, ui) {
if (withvalue == true) {
$("#" + $(this).attr("id") + "_val").val(ui.item.thevalue);
//$("#" + $(this).attr("id") + "_val").trigger("change");
}
// Update hidden on select option
$("#" + $(this).attr("id") + "_id").val(ui.item.id);
// For items that have change event bound trigger ot so we are updating data in table.
$("#" + $(this).attr("id") + "_id").trigger("change");
},
focus: function (event, ui) {
// Save old value for backup
previous = this.value;
},
change: function (event, ui) {
//alert($(this).val());
if (!ui.item && $(this).val().length > 0) { // Item not selected in the dropdown list
$.ajax({
url: "ajax/check_dropdown_item_exists.php",
global: false,
method: "POST",
data: {
table: createtable,
colnames: createcolumn,
colvals: encodeURI(String($(this).val().toUpperCase())),
},
success: function (data) {
if (data != "TRUE") {
// Ask confirm to add new item to table
$.confirm('ITEM DOES NOT EXIST! ADD TO LIST?', function (answer) {
if (answer) {
$.ajax({
url: "inc/insert_table_field.php",
global: false,
method:"POST",
data: {
table: createtable,
colnames: createcolumn,
colvals: String($(this).val().toUpperCase()),
retid: retid,
},
success: function (data) {
if ($.isNumeric(data)) {
$("#" + $(element).attr("id") + "_id").val(data);
// Set the newly created value in dropdown
//$(element).val(String($(element).val().toUpperCase()));
// And update DB
$("#" + $(element).attr("id") + "_id").trigger("change");
} else {
$.alert(data);
}
},
error: function () {
$.alert('ERROR CREATING THE NEW ITEM!');
}
})
} else {
alert(previous)
// NO so blank
$(this).val(previous).focus();
}
})
} else {
// Commit change with value that already exists
// fecth item id and trigger select event
$.ajax({
url: "ajax/get_dropdown_item_id.php",
global: false,
method: "POST",
data: {
table: createtable,
colnames: createcolumn,
colvals: String($(element).val().toUpperCase()),
retid: retid,
},
success: function (data) {
if ($.isNumeric(data)) {
$("#" + $(element).attr("id") + "_id").val(data);
$("#" + $(element).attr("id") + "_id").trigger("change");
}
}
})
}
}
})
} else {
$(this).val((ui.item ? ui.item.label : "")); // If empty put back the last one
if (!ui.item) {
if (deleteoption !== true) {
this.value = "";
$.alert('YOU CAN SELECT FROM DROPDOWN ONLY!');
$(element).val(element.oldvalue).focus();
} else {
$("#" + $(this).attr("id") + "_id").val("");
$("#" + $(this).attr("id") + "_id").trigger("change");
}
}
}
}
}).dblclick(function () {
$(this).autocomplete("search", "");
}).click(function () {
$(this).autocomplete("search", "");
})
}
问题是焦点不会对文本框/输入的焦点做出反应,而是自动完成的结果
这意味着,当您在文本框中单击时,仅当您选择一个结果时,功能焦点才会启动
要获得之前的信息,最好的解决方案是:
$(your element).click(function() {
previous = $(this).val()
}
这来自jQueryUi Autocomplete的文档:
焦点(事件、用户界面)
焦点移动到项目时触发(未选择)。默认操作是将文本字段的值替换为焦点项目的值,但前提是事件是由键盘交互触发的。
取消此事件会阻止更新值,但不会阻止聚焦菜单项。
您甚至还没有描述问题是什么您可以添加一个JSFIDLE吗?