我在 type script 上有一堂课:
export class Child {
name:string;
age:number;
}
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我想强制类实例只具有类声明所具有的属性。
例如,如果我从 firebase 获取一个对象:
myFirebaseService.getChild(id).then(function(child){
var currentChild = new Child(child);
})
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所以当对象是:{name:"ben", color:"db"} 时,我希望结果是:
currentChild = {"name":"ben"}
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因为“颜色”不是“孩子”的领域。
我试过这个:
export class Child {
name:string;
age:number;
constructor(tempChild:Child = null) {
if (tempChild){
for (var prop in tempChild) {
this[prop] = tempChild[prop];
}
}
}
}
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但它没有帮助。“currentChild”获取所有字段并将它们附加到类实例。
(当然,我可以使用以下代码:
export class Child {
name:string;
age:number;
constructor(tempChild:Child = null) {
if (tempChild){
this.nam = tempChild.name;
this.age =tempChild.ageÏ;
}
}
}
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,但我的真理课有很多字段,我想要短代码)
我在 React-Redux 项目工作。我使用 ag-grid 并且有问题。
我到达控制台:
Uncaught TypeError: Object prototype may only be an Object or null: undefined
at setPrototypeOf (<anonymous>)
at __extends (eval at <anonymous> (bundle.js:13399), <anonymous>:8:9)
at eval (eval at <anonymous> (bundle.js:13399), <anonymous>:28:5)
at eval (eval at <anonymous> (bundle.js:13399), <anonymous>:301:2)
at Object.<anonymous> (bundle.js:13399)
at __webpack_require__ (bundle.js:556)
at fn (bundle.js:87)
at eval (eval at <anonymous> (bundle.js:13390), <anonymous>:14:19)
at Object.<anonymous> (bundle.js:13390)
at __webpack_require__ (bundle.js:556)
at fn (bundle.js:87)
at eval (eval at <anonymous> (bundle.js:13255), <anonymous>:10:24)
at Object.<anonymous> (bundle.js:13255)
at __webpack_require__ (bundle.js:556) …Run Code Online (Sandbox Code Playgroud) 我正在研究ionic2项目.我使用离子选择元素.
我搜索了一种方法,以编程方式关闭选择框选择任何项目(而不是等待用户按OK).
<ion-select id="select" #select>
<ion-option (ionSelect)="closeAndSave()" *ngFor="let option of enumList" [value]="option">{{ option}}</ion-option>
</ion-select>
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`
class myClass{
@viewChild('select') select:Select;
closeAndSave(){
/*it is come here on press any option. but how can I close here my select element? I tried: this.select.destroy() - not do any thing. any solution?*/
}
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`
我在durandal项目工作.我在html中有span和button元素.我想在点击按钮时显示跨度.我的问题是,当我从html隐藏跨度时 - 它无法从javascript中显示它.我在你的网站上看到了这个问题(使用jquery链接更改标签标签的可见性),我尝试了所有的答案 - 任何帮助我.
(我尝试使用: in html:
<span id="mySpan" hidden = "hidden">aaa</span>
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要么:
<span id="mySpan" style= "visibility:collapse">aaa</span>
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要么:
<span id="mySpan" style= "display:none">aaa</span>
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在javascript中:
$("#mySpan").show();
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要么:
$("#mySpan").css('visibility', 'visible');
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我尝试了所有可选组合 )
注意:我希望您知道,当我不隐藏HTML的范围,并尝试使用toggle()时hide(),show()- 它运行良好.
不起作用的例子:
在html页面上:
<span id="mySpan" hidden = "hidden">aaa</span>
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在javascript页面上:
$("#mySpan").show();
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ag-grid ×1
constructor ×1
css ×1
durandal ×1
html ×1
ionic2 ×1
jquery ×1
npm ×1
react-redux ×1
typescript ×1