我看了很多教程，但我不知道如何做到这一点只能输入数字型，这是输入作出淘汰赛
input(type="text",name="price",id="price"data-bind="text: price,valueUpdate:['afterkeydown','propertychange','input']")
，这是我的ViewModel
price: ko.computed(function()
{
return parseFloat(this.replace(' ','').replace(/[^0-9\.]+/g,"")) || '';
},this)
但这导致错误：这没有方法替换？我如何将价格值传递给计算函数？
最好创建自定义绑定http://knockoutjs.com/documentation/custom-bindings.html，它只接受允许的字符[0-9 ,.]作为数字表示。
，就把这行到你的观点
<input id="text" type="text" data-bind="numeric, value: number">
，就把这行到你的模型（记得要结合作为观察的特性数）
ko.bindingHandlers.numeric = {
init: function (element, valueAccessor) {
$(element).on("keydown", function (event) {
// Allow: backspace, delete, tab, escape, and enter
if (event.keyCode == 46 || event.keyCode == 8 || event.keyCode == 9 || event.keyCode == 27 || event.keyCode == 13 ||
// Allow: Ctrl+A
(event.keyCode == 65 && event.ctrlKey === true) ||
// Allow: . ,
(event.keyCode == 188 || event.keyCode == 190 || event.keyCode == 110) ||
// Allow: home, end, left, right
(event.keyCode >= 35 && event.keyCode <= 39)) {
// let it happen, don't do anything
return;
}
else {
// Ensure that it is a number and stop the keypress
if (event.shiftKey || (event.keyCode < 48 || event.keyCode > 57) && (event.keyCode < 96 || event.keyCode > 105)) {
event.preventDefault();
}
}
});
}
};
这真的有用吗？对我来说，它不会更新Observable，如果它在用户界面的某个地方？例如，您有如上所述的以及一些。在这种情况下，如果用户在输入内编辑编号，编辑完成后UI不会更新。 – renathy
从输入字段更改焦点后将应用更改。下面是实时编辑的简单示例（无焦点更改）。 http://jsfiddle.net/jakethashi/L7UEm/ –
@renathy我离开了textInput绑定，并添加了数字作为第二个绑定，效果很好 – LobsterMan
的另一种方法：我发现，剔除效果很好结合jQuery-validate。您只需确保在尝试使用数字值之前验证表单。
假设你有一个表单DOM元素，你可以设置通过
$(".yourform").validate({
rules: {
year: {
digits: true,
minlength: 4,
maxlength: 4
}
},
messages: {
year: "Please enter four digits (e.g. 2009).",
}
});
在您的视图模型设置了双向绑定像往常一样，例如验证规则通过self.year = ko.observable("")。现在请确保您在进一步处理self.year()之前致电$(".yourform").valid()。在我的情况下，我在做var year = parseInt(self.year(), 10)。在表单验证之后，预计这将始终产生有意义的结果。
淘汰赛有这个扩展。来自knockoutjs.com的Check This解释了如何使用可观察的扩展器来强制输入为数字。我粘贴代码从这里的文档：
源代码：查看
<p><input data-bind="value: myNumberOne" /> (round to whole number)</p>
<p><input data-bind="value: myNumberTwo" /> (round to two decimals)</p>
源代码：查看模式
ko.extenders.numeric = function(target, precision) {
//create a writable computed observable to intercept writes to our observable
var result = ko.pureComputed({
read: target, //always return the original observables value
write: function(newValue) {
var current = target(),
roundingMultiplier = Math.pow(10, precision),
newValueAsNum = isNaN(newValue) ? 0 : parseFloat(+newValue),
valueToWrite = Math.round(newValueAsNum * roundingMultiplier)/roundingMultiplier;
//only write if it changed
if (valueToWrite !== current) {
target(valueToWrite);
} else {
//if the rounded value is the same, but a different value was written, force a notification for the current field
if (newValue !== current) {
target.notifySubscribers(valueToWrite);
}
}
}
}).extend({ notify: 'always' });
//initialize with current value to make sure it is rounded appropriately
result(target());
//return the new computed observable
return result;
};
function AppViewModel(one, two) {
this.myNumberOne = ko.observable(one).extend({ numeric: 0 });
this.myNumberTwo = ko.observable(two).extend({ numeric: 2 });
}
ko.applyBindings(new AppViewModel(221.2234, 123.4525));
<input type="text" id="alpha-validation" data-bind="value: YourDataName, valueUpdate: 'afterkeydown' , event: { 'input': AlphaCheck}" style="text-transform:uppercase">
创建AlphaCheck功能，并添加。
$('#alpha-validation').keyup(function() {
if (this.value.match(/[^0-9 ]/g)) {
this.value = this.value.replace(/[^0-9 ]/g, '');
}
});
这将起作用！
我知道这个问题是一岁，但让我发布此为页面的功能游客着想。
检查了这一点：
ko.bindingHandlers.numericnumbers = {
init: function (element) {
$(element).on('keypress', function (number) {
number = (number) ? number : window.event;
var charcode = (number.which) ? number.which : number.keyCode;
if (charcode > 31 && (charcode < 48 || charcode > 75))
number.preventDefault();
});
}};
创建您的数据绑定在你的闪闪发光的新代码指向：
<input id="price" name="price" type="text" data-bind="numeric">
崭新的淘汰赛代码：
price = ko.observable();
price.subscribe(function(newValue) {
price = newValue.replace(/[\D\.]/g, '');
});
这意味着每当你更新价格时，它会应用函数中的逻辑（在这种情况下剥离出任何东西不是数字或期限），并将其直接应用于价格。您还可以在这里添加其他验证或很酷的功能，比如在开始添加货币sybmol，维持到小数点后2位，等等...
用“的keydown”事件的帮助下，我们可以限制在文字等关键的应该包含数字值的框。
$(document).ready(function(){
$("selector").on("keydown", function (e) {
//numbers, delete, backspace, arrows
var validKeyCodes = [8, 9, 37, 38, 39, 40, 46, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57];
if (!($.inArray(e.keyCode, validKeyCodes) >= 0))
e.preventDefault();
});
});
我们可以限制用户输入用户超过两位十进制数字。 23.81，3452.83修改后的代码如下。参考代码来自@Martin Surynek答案。
HTML -
<p>
<input data-bind="value: myNumberOne" /> (round to whole number)</p>
<p>
<input data-bind="num, value: myNumberTwo" /> (round to two decimals)</p>
脚本 -
<script>
ko.bindingHandlers.num = {
init: function (element, valueAccessor) {
$(element).on("keypress", function (event) {
//debugger
console.log(event.keyCode);
var $this = $(this);
var text = $this.val();
// Stop insert two dots
if ($this.val().indexOf('.') != -1 && (event.which == 190 || event.which == 110)) {
event.preventDefault();
}
// Allow: backspace, delete, tab, escape, and enter
if (event.keyCode == 46 || event.keyCode == 8 || event.keyCode == 9 || event.keyCode == 27 || event.keyCode ==
13 ||
// Allow: Ctrl+A
(event.keyCode == 65 && event.ctrlKey === true) ||
// Allow: . ,event.keyCode == 188 ||
(event.keyCode == 190 || event.keyCode == 110) ||
// Allow: home, end, left, right
(event.keyCode >= 35 && event.keyCode <= 39)) {
// let it happen, don't do anything
return;
}
// Ensure that it is a number and stop the keypress
if (event.shiftKey || (event.keyCode < 48 || event.keyCode > 57) && (event.keyCode < 96 || event.keyCode >
105)) {
event.preventDefault();
}
if ((event.which == 46) && (text.indexOf('.') == -1)) {
setTimeout(function() {
if ($this.val().substring($this.val().indexOf('.')).length > 3) {
$this.val($this.val().substring(0, $this.val().indexOf('.') + 3));
}
}, 1);
}
if ((text.indexOf('.') != -1) &&
(text.substring(text.indexOf('.')).length > 2) &&
(event.which != 0 && event.which != 8) &&
($(this)[0].selectionStart >= text.length - 2)) {
event.preventDefault();
}
//console.log($(this)[0].selectionStart >= text.length - 2);
});
}
};
ko.extenders.numeric = function (target, precision) {
//create a writable computed observable to intercept writes to our observable
var result = ko.pureComputed({
read: target, //always return the original observables value
write: function (newValue) {
var current = target(),
roundingMultiplier = Math.pow(10, precision),
newValueAsNum = isNaN(newValue) ? 0 : parseFloat(+newValue),
valueToWrite = Math.round(newValueAsNum * roundingMultiplier)/roundingMultiplier;
//only write if it changed
if (valueToWrite !== current) {
target(valueToWrite);
} else {
//if the rounded value is the same, but a different value was written, force a notification for the current field
if (newValue !== current) {
target.notifySubscribers(valueToWrite);
}
}
}
}).extend({
notify: 'always'
});
//initialize with current value to make sure it is rounded appropriately
result(target());
//return the new computed observable
return result;
};
function AppViewModel(one, two) {
this.myNumberOne = ko.observable(one).extend({
numeric: 0
});
this.myNumberTwo = ko.observable(two).extend({
numeric: 2
});
}
ko.applyBindings(new AppViewModel(221.2234, 123.4525));
</script>
我也有类似的问题。
我还需要确保只有内部值，对于IE9和以上（因此type = numberical是不够的），并且由于我们有很多国际客户，所以我不能依赖键码，因此以下是我结束了：
//In my js class method (self is this as usual)
self.ensureNumberical = function (data, e) {
var keyValue = e.key;
if (keyValue.match(/[0-9]/g)) {
return true;
}
return false;
}
//In my MVC View
data-bind="event: { keypress: ensureNumberical }"
而不是'input type =“text”'，如果将其更改为'input type =“number”'，该怎么办？我认为这些限制你将它们放入数值中。 – jonhopkins
type =“number”与某些浏览器的兼容性较差 – andrescabana86
Jon是正确的，因为您可以将类型更改为数字，但如果我没有记错，并非所有浏览器都支持该类型。例如，我相信任何事情之前，IE10让你把课文中有没有问题 –