我正在使用AngularJs，HTML和PHP编写和应用程序。在应用程序中，我有一个下拉列表，当选择一个选项时，表中会填充从数据库中提取的相关数据。我可以添加或删除表中的信息。这非常有效。但是，我遇到的挑战是，每次编辑表时，都会重新加载网页刷新/路由，并且下拉列表会返回其默认值。这样做的结果是用户必须手动重新选择下拉列表值以执行表上的每个操作。 如何更改代码以保留/保留最后选择的选项值并在网页/路由重新加载时选择所述下拉列表选项？
我看到许多帮助响应设置下拉列表的初始默认值。然而，这不是我想要实现的目标。我正在尝试在网页重新加载后设置后重新加载值或值。
以下是我尝试过的部分内容。我正试图弄清楚这一点。任何帮助表示赞赏。
修改
问题解决了 更改前的HTML
<select id="b_year" ng-options="b.year for b in budgets track by b.year" ng-model="b.selectedBudget" ng-change="getBudgetItems(b.selectedBudget.year)" required><option value="">-- Choose budget year --</option></select>
HTML解决方案更改
<select id="b_year" ng-options="b.year for b in budgets" ng-model="b.selectedBudget" ng-init="b.selectedBudget" ng-selected="getBudgetItems(b.selectedBudget.year)" required><option value="">-- Choose budget year --</option></select>
更改前的控制器代码段
$scope.reloadRoute();
$scope.items.push({'line_item': li.line_item, 'weight': li.weight, 'allocated': li.allocated});
localStorage['b_year'] = year; //Store the selected year in local storage for later use
budget_size = server.getBudgetSize();
for(var i = 0; i < budget_size; i++){
if($scope.budgets[i].year === localStorage['b_year']){
$scope.b.selectedBudget[i] = localStorage['b_year'];
}else{
}
}
带解决方案变更的控制器
app.controller(.... {
....
(function(){
$http.get( //Get info on budgets
"http://localhost/TrGway/getbudgetinfo.php"
)
.success(function(data){
$scope.budgets = data.budgets;
for(var i = 0; i < data.budgets.length; i++){
if($scope.budgets[i].year === selectedYear){
$scope.b = {};
$scope.b.selectedBudget = $scope.budgets[i];
}
}
})
.error(function(data){
$scope.message = "Error!! Getting Budget Info Failed: " + data;
});
})();
....
$scope.$watch("b.selectedBudget.year", function(item) {
localStorage.setItem("selectedYear", item);
});
});
App.controller('budgetCtrl', ['$scope', '$http', '$location', '$window', '$route', 'BudgetService', function($scope, $http, $location, $window, $route, BudgetService){
(function(){
$http.get( //Get info on budgets
"http://localhost/TrGway/getbudgetinfo.php"
)
.success(function(data){
server.setBudgets(data.budgets);//Set the budget info in the BudgetService for
//later usage anywhere in the program;
$scope.budgets = data.budgets;
budget_size = server.getBudgetSize();
server.getBudgetInfo();
})
.error(function(data){
$scope.message = "Error!! Getting Budget Info Failed: " + data;
});
})();
(function(){ //Get Line Items Info to populate the table
$http.get(
"http://localhost/TrGway/lineItemInfo.php"
)
.success(function(data){
server.setLineItems(data.items);
$scope.items = data.items;
server.getLineItemsInfo();
})
.error(function(data){
$scope.message = "Error!! Getting Line Items Info Failed: "+data;
});
})();
$scope.addBudget = function(budget){
if( budget.year < new Date().getFullYear() ){
alert("Budgets cannot be created retroactively.\n\
\nPlease enter a budget year greater than "+ new Date().getFullYear() );
$scope.budget.year = "";
}else{
server.addBudget(budget);
server.getBudgetInfo();
$scope.budgets = server.getBudgets();
$scope.budget = {};//Clear the add budget form
}
};
$scope.getBudgetItems = function(year){
/*This is where info on the budget for the selected year is retrieved and passed to the table
This works great every time*/
if( year === undefined ){ //If no year is selected do nothing
$scope.budget_amount = 0;
$scope.budget_amount_used = 0;
$scope.budget_amount_remaining = 0;
}else{
Budgets = server.getBudgets();
budget_size = server.getBudgetSize();
for(var i = 0; i < budget_size; i++){
if(Budgets[i].year === year){
$scope.budget_amount = Budgets[i].starting_amount;
$scope.budget_amount_used = Budgets[i].amount_used;
$scope.budget_amount_remaining = Budgets[i].running_balance;
amount_remaining = Budgets[i].starting_amount - Budgets[i].amount_used;
percent_used += (Budgets[i].amount_used / Budgets[i].starting_amount * 100);
server.setSelectedBudget(Budgets[i]);
}else{
//$scope.budget_amount = 0;
}
}
server.setPercentUsed(percent_used);
server.setPercentRemaining( 100 - percent_used);
server.setAmountRemaining(amount_remaining);
}
};
/*======================= THIS IS WHERE THE CHALLENGE IS ====================*/
$scope.addLineItem = function(li, b){
/*This is where the List items are added to the table before page reload*/
if(($scope.budget_amount_used-0 + li.allocated-0) > $scope.budget_amount){
alert("Budgeted amount exceeded!!!\nPlease consider revising");
$location.path('editbudget');
$scope.li.weight = 0;
$scope.li.allocation = 0;
}else{
server.setSelectedBudgetYear(b.selectedBudget.year); //Save selected year to a variable
server.addLineItem(li, b); //Add the new Line items row to database
$scope.reloadRoute();
$scope.items.push({'line_item': li.line_item, 'weight': li.weight, 'allocated': li.allocated});
$scope.b = {};
//$scope.b.selectedBudget = localStorage.getItem("selected");
$scope.$watch("b.selectedBudget.year", function(item) {
localStorage.setItem("selected", item);
});
//$scope.b.selectedBudget.year = server.getSelectedBudgetYear(); //I tried this also
}
$scope.li.line_item = "";
$scope.li.weight = 0;
$scope.li.allocation = 0;
$scope.b.selectedBudget = localStorage.getItem("selected");
/* LEAVING THIS SO YOU CAN SEE WHAT ELSE I HAVE TRIED
$scope.b = {};
$scope.b.selectedBudget = localStorage.getItem("selectedBudget");
$scope.watch("b.selected", function(item) {
localStorage.setItem("selected", item);
});
$scope.b.selectedBudget = localStorage['b_year'];
*/
/* LEAVING THIS SO YOU CAN SEE WHAT ELSE I HAVE TRIED
budget_size = server.getBudgetSize();
for(var i = 0; i < budget_size; i++){
if($scope.budgets[i].year === server.getSelectedBudgetYear()){
$scope.b.selectedBudget.year = server.getSelectedBudgetYear();
}else{
}
}*/
};
$scope.deleteLineItem = function(row, b){
$http({
method: "post",
url: "http://localhost/TrGway/deleteLineItem.php",
crossDomain: true,
data:{
'seq': row.seq,
'year': row.year,
'allocated':row.allocated,
'starting_amount': b.selectedBudget.starting_amount,
'amount_used': b.selectedBudget.amount_used,
'running_balance': b.selectedBudget.running_balance
},
headers: {
'Content-Type': 'application/x-www-form-urlencoded'
}
})
.success(function(response){
if(response.toString() === "success"){
var index = -1;
var itemsArr = eval( $scope.items );
for( var i = 0; i < itemsArr.length; i++ ) {
if( itemsArr[i].seq === row.seq ) {
index = i;
break;
}
}
if( index === -1 ) {
alert( "Something has gone wrong!!\nLine item was not deleted.\nPlease try again" );
}
server.reset();
server.reload();
$scope.budget_percent_used = server.getPercentUsed()-0;
$scope.budget_percent_remaining = server.getPercentRemaining()-0;
$scope.budget_amount_used = server.getAmountUsed()-0;
$scope.budget_amount_remaining = server.getAmountRemaining()-0;
server.setTotalWeighting($scope.totalweighting + row.weight)-0;
server.setPercentUsed(server.getTotalWeighting())-0;
server.setPercentRemaining(100 - server.getPercentUsed())-0;
$scope.items.splice( index, 1 ); //Remove the row with matching index/seq value
$scope.totalweighting = server.getTotalWeighting();
$scope.budget_percent_used = server.getPercentUsed()-0;
$scope.budget_percent_remaining = server.getPercentRemaining()-0;*/
$scope.reloadRoute();
}else{ //If deleting the line item failed
$location.path('editbudget');
$scope.budgetmessage = "Line Item Update Failed: "+response;
}
})
.error(function(response){ //If there was an error connecting to the server
$scope.budgetmessage = "Error!! Updating Line Item Failed: "+response;
});
row.isEditing = false;
};
$scope.updateLineItem = function(row){
$http({
method: "post",
url: "http://localhost/TrGway/updateLineItem.php",
crossDomain: true,
data:{
'seq': row.seq,
'line_item': row.line_item,
'weight': row.weight,
'allocated': row.allocated
},
headers: {
'Content-Type': 'application/x-www-form-urlencoded'
}
})
.success(function(response){
if(response.toString() === "success"){
$location.path('editbudget');
}else{
$location.path('editbudget');
$scope.budgetmessage = "Line Item Update Failed: "+response;
}
})
.error(function(response){
$scope.budgetmessage = "Error!! Updating Line Item Failed: "+response;
});
row.isEditing = false;
};
$scope.cancelLineItemEditing = function(row){
row.isEditing = false;
};
$scope.updateBudget = function(b){
$http({
method: "post",
url: "http://localhost/TrGway/updatebudget.php",
crossDomain: true,
data:{
'year': b.selectedBudget.year,
'starting_amount': b.edit_starting_amount
},
headers: {
'Content-Type': 'application/x-www-form-urlencoded'
}
})
.success(function(response){
if(response.toString() === "success"){
server.setStartingAmount(b.edit_starting_amount);
var line_items = server.getLineItems();
var start_amount = server.getStartingAmount();
var total_weight = 0;
var amount_used = 0;
var amount_remaining = 0;
var percent_used = 0;
var percent_remaining = 0;
for(var i = 0; i < line_items.length; i++){
//Update the line items on the page immediately
line_items[i].weight = ( line_items[i].allocated / start_amount) * 100;
total_weight += line_items[i].weight;
amount_used += line_items[i].allocated-0;
//Update the line items in the database immediately
$scope.updateLineItem(line_items[i]);
}
server.load();
percent_used = ( amount_used / start_amount) * 100;
amount_remaining = start_amount - amount_used;
percent_remaining = 100 - percent_used;
server.setLineItems(line_items);
server.setTotalWeighting(total_weight);
server.setAmountUsed(amount_used);
server.setPercentUsed(percent_used);
server.setAmountRemaining(amount_remaining);
server.setPercentRemaining(percent_remaining);
$scope.items = server.getLineItems();
$scope.total = 0;
$scope.total = server.getStartingAmount();
$scope.totalweighting = server.getTotalWeighting()-0;
$scope.budget_amount_used = server.getAmountUsed()-0;
$scope.budget_percent_used = server.getPercentUsed()-0;
$scope.budget_percent_remaining = server.getPercentRemaining()-0;
$scope.budget_amount_remaining = server.getAmountRemaining()-0;
$location.path('editbudget');
}else{
$location.path('editbudget');
$scope.budgetmessage = "Budget Update Failed: "+response;
}
})
.error(function(response){
$scope.budgetmessage = "Error!! Updating Budget Failed: "+response;
});
$scope.b = {};
};
$scope.reloadRoute = function(){
$route.reload();
server.reload();
//alert('Loaded!!');
};
}]);<div class="breadcrumbs" id="breadcrumbs">
<ul class="breadcrumb">
<li>Home</li>
<li class="active"><a href="">Add/Edit line Items</a></li>
<li style="float: right" ng-controller="authCtrl"><a ng-click="logout();">Logout</a></li>
<li style="float: right"><a href="#/dashboard">Back</a></li>
</ul>
</div>
<div class="row" ng-cloak="" ng-controller="budgetCtrl">
<div class="col-md-5">
<section>
<form name="LineItemForm" class="form-horizontal" role="form">
<fieldset>
<table class="table table-striped">
<thead>
<tr>
<th style="width: 150px" colspan="1">Select Budget Year To Edit Line Items</th>
</tr>
</thead>
<tbody>
<tr>
<td colspan="1">
<div class="col-md-7">
<!-- THIS IS WHERE THE YEAR IS SELECTED -->
<select id="b_year" ng-options="b.year for b in budgets track by b.year" ng-model="b.selectedBudget" ng-change="getBudgetItems(b.selectedBudget.year);" ng-selected="" required>
<option value="">-- Choose budget year --</option>
</select>
</div>
</td>
</tr>
<tr>
<th style="width: 150px" colspan="1">{{b.budgetmessage}}</th>
</tr>
<tr>
<td>
<h3>Add Line Item Here</h3>
<div class="form-group">
<label class="col-md-3 control-label no-padding-right" for="line_item">Line Item</label>
<div class="col-md-7">
<input type="text" class="form-control" name="line_item" id="line_item" ng-model="li.line_item" ng-disabled="!b.selectedBudget" required/>
</div>
</div>
<div class="form-group">
<label class="col-md-3 control-label no-padding-right" for="weight">weighting %</label>
<div class="col-md-7">
<input type="number:2" class="form-control" name="weight" id="weight" ng-init="li.weight = 0" ng-model="li.weight" ng-disabled="!b.selectedBudget || !li.line_item || li.line_item.length<5" required/>
</div>
</div>
<div class="form-group">
<label class="col-md-3 control-label no-padding-right" for="allocated">Allocated $</label>
<div class="col-md-7">
<input type="number:2" class="form-control" name="allocated" id="allocated" placeholder="{{li.allocated = (budget_amount * li.weight) / 100 | currency}}" ng-init="li.allocated=0" ng-model="li.allocated" ng-disabled="!b.selectedBudget || !li.weight" required />
</div>
</div>
<div class="form-group" style="padding-right: 100px;">
<span class="lbl col-sm-5"> </span>
<div class="col-md-7 message" >
<span id="message" class="block input-icon input-icon-right">{{message}}</span>
</div>
</div>
<div class="form-group">
<div style="padding-right:100px">
<button type="submit" class="width-35 pull-right btn btn-sm btn-primary" ng-click="addLineItem(li, b)" data-ng-disabled="LineItemForm.$invalid || li.weight===0 || li.line_item.length < 5">
Add Line Item
</button>
</div>
</div>
</td>
</tr>
</tbody>
</table>
</fieldset>
</form>
</section>
</div>
<div>
<section>
<div class="col-lg-14" style="float: right">
<form>
<fieldset>
<table class="table table-striped" >
<thead>
<tr>
<!--<th>Index</th>-->
<th>Line Items</th><th style="width: 150px">% Weighting</th><th style="width: 150px">Allocation $</th><th style="width: 120px">Tasks</th><!---->
</tr>
</thead>
<tbody>
<tr data-ng-repeat="row in items" ng-model="items" ng-if="row.year === b.selectedBudget.year"><!--<td>{{$index+1}}</td>-->
<td title="'Line Item'" ng-switch="row.isEditing" ng-class="line_item.$dirty ? 'bg-warning' : ''" ng-form="name" demo-tracked-table-cell>
<span ng-switch-default class="editable-text">{{row.line_item}}</span>
<div class="controls" ng-class="line_item.$invalid && line_item.$dirty ? 'has-error' : ''" ng-switch-when="true">
<input type="text" name="line_item" ng-model="row.line_item" class="editable-input form-control input-sm" required />
</div>
</td>
<td>{{ row.weight = row.allocated / budget_amount * 100 | number: 2 }}</td>
<td title="'Allocation'" ng-switch="row.isEditing" ng-class="allocated.$dirty ? 'bg-warning' : ''" ng-form="allocated" demo-tracked-table-cell>
<span ng-switch-default class="editable-text">{{ row.allocated | currency }}</span>
<div class="controls" ng-class="allocated.$invalid && allocated.$dirty ? 'has-error' : ''" ng-switch-when="true">
<input type="text" name="allocated" ng-model="row.allocated" class="editable-input form-control input-sm" required/>
</div>
</td>
<td>
<button class="btn btn-primary btn-sm" ng-click="updateLineItem(row)" ng-if="row.isEditing" ng-disabled="rowForm.$pristine || rowForm.$invalid"><span class="glyphicon glyphicon-ok"></span></button>
<button class="btn btn-default btn-sm" ng-click="cancelLineItemEditing(row)" ng-if="row.isEditing"><span class="glyphicon glyphicon-remove"></span></button>
<button class="btn btn-default btn-sm" ng-click="row.isEditing = true" ng-if="!row.isEditing"><span class="glyphicon glyphicon-pencil"></span></button>
<button class="btn btn-danger btn-sm" ng-click="deleteLineItem(row, b)" ng-if="!row.isEditing"><span class="glyphicon glyphicon-trash"></span></button>
</td>
</tr>
<tr>
<td>
<h5>
<span class="block input-icon input-icon-right">
<b>TOTAL (Budget Estimate)</b>
</span>
</h5>
</td>
<td>
<h5>
<span class="block input-icon input-icon-right">
<b>{{ totalweighting = budget_amount > 0 ? 100 : 0 | number:2 }}%</b><!---->
</span>
</h5>
</td>
<td>
<h5>
<span class="block input-icon input-icon-right">
<b>{{ budget_amount | currency }}</b>
</span>
</h5>
</td><td></td>
</tr>
<tr>
<td>
<h5>
<span class="block input-icon input-icon-right">
<b>BUDGET AMOUNT USED</b>
</span>
</h5>
</td>
<td>
<h5>
<span class="block input-icon input-icon-right">
<b>{{ budget_percent_used = budget_amount_used > 0 ? budget_amount_used * 100/budget_amount : 0 | number:2 }}%</b>
<!--Adding the -0 forces the compiler to treat the value as a number-->
</span>
</h5>
</td>
<td>
<h5>
<span class="block input-icon input-icon-right">
<!--{{ budget_amount_used + li.allocated | currency }}-->
<b>{{ budget_amount_used | currency }}</b>
</span>
</h5>
</td><td></td>
</tr>
<tr>
<td>
<h5>
<span class="block input-icon input-icon-right">
<b>BUDGETED AMOUNT REMAINING</b>
</span>
</h5>
</td>
<td>
<h5>
<span class="block input-icon input-icon-right">
<b>{{ budget_percent_remaining = 100 - budget_percent_used | number:2 }}%</b>
<!--Adding the -0 forces the compiler to treat the value as a number-->
</span>
</h5>
</td>
<td>
<h5>
<span class="block input-icon input-icon-right">
<!--{{ budget_amount_remaining - li.allocated | currency }}-->
<b>{{ budget_amount_remaining | currency }}</b>
</span>
</h5>
</td><td></td>
</tr>
</tbody>
</table>
</fieldset>
</form>
</div>
</section>
</div>
</div>
答案 0 :(得分：1)
我会做这样的事情：
app.controller(.... {
....
$scope.b = {};
$scope.b.selected = localStorage.getItem("selected");
$scope.watch("b.selected", function(item) {
localStorage.setItem("selected", item);
});
....
});
修改的
因此我们怀疑初始值会被某处覆盖。以下是如何调试它的一些帮助：您可以在$scope.b上定义属性设置器，它可以提醒或中断调试器。使用这样的东西：
$scope.b = {
set selectedBudget(v) {
debugger;
// or alert(1);
}
};
答案 1 :(得分：0)
解决方案
这是我提出的解决方案，以便在网页刷新后保持下拉列表选择。我希望这会对某人有所帮助。我添加了评论来帮助解释我的所作所为。我希望他们很清楚。但是，我欢迎任何更正或澄清。我得到了这个解决方案，感谢@Tamas Hegedus的帮助，他指出了我正确的方向。
app.controller(.... {
....
(function(){
$http.get( //Get info on budgets
"http://localhost/TrGway/getbudgetinfo.php"
)
.success(function(data){
$scope.budgets = data.budgets; //assign array of elements to the scope variable
for(var i = 0; i < data.budgets.length; i++){ //Loop through each array element
if($scope.budgets[i].year === selectedYear){ //Check if any of the 'year' value in the array match the value stored in localStorage
$scope.b = {}; //reset the selected scope variable
$scope.b.selectedBudget = $scope.budgets[i]; //Assign the array element with the matching year, as the selected scope element
}
}
})
.error(function(data){
$scope.message = "Error!! Getting Budget Info Failed: " + data;
});
})();
....
$scope.$watch("b.selectedBudget.year", function(item) { //Set watch on array element 'year' for changes/selection
localStorage.setItem("selectedYear", item); //When an element is selected from the drop down list, its value is stored in localStorage
});
});<select id="b_year" ng-options="b.year for b in budgets" ng-model="b.selectedBudget" ng-selected="getBudgetItems(b.selectedBudget.year)" required><option value="">-- Choose budget year --</option></select>