如何从文本输入框保存值，然后在Dart中加载它？ [英] How do I save a value from a text input box and load it later, in Dart?

问题描述

（来自邮件列表）

如何创建某种类型的文本输入框，这将允许我保存该文本，并在以后的代码中使用它？我使用Dart。

解决方案

使用InputElements和HTML5本地存储的组合。 Dart中的Storage接口实现了Map，因此您可以将键/值对存储为字符串。

HTML：

< pre class =lang-dart prettyprint-override> < p>
从本地存储：< output id =username-output>< / output>
< / p>

< label for =username>用户名：< / label>
< input type =textname =usernameid =username>
< input type =submitid =savevalue =Save>


Dart：

  import'dart：html'; 
 
 void main（）{
 InputElement username = query（'＃username'）; 
 InputElement submit = query（'＃save'）; 
元素output = query（'＃username-output'）; 
 Storage localStorage = window.localStorage; 
 
 String savedUsername = localStorage ['username']; 
 if（savedUsername！= null）{
 output.text = savedUsername; 
} 
 
 submit.onClick.listen（（Event e）{
 output.text = username.value; 
 localStorage ['username'] = username.value ; 
}）; 
} 
  

(from the mailing list)

How do I create some sort of text input box that will allow me to save that text and use it later in the code? I am using Dart.

解决方案

Use a combination of InputElements and HTML5 Local Storage. The Storage interface in Dart implements Map, so you can store key/value pairs as strings.

The HTML:

<p>
From local storage: <output id="username-output"></output>
</p>

<label for="username">Username:</label>
<input type="text" name="username" id="username">
<input type="submit" id="save" value="Save">

The Dart:

import 'dart:html';

void main() {
  InputElement username = query('#username');
  InputElement submit = query('#save');
  Element output = query('#username-output');
  Storage localStorage = window.localStorage;

  String savedUsername = localStorage['username'];
  if (savedUsername != null) {
    output.text = savedUsername;
  }

  submit.onClick.listen((Event e) {
    output.text = username.value;
    localStorage['username'] = username.value;
  });
}

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