如何在重新加载网页后在 JavaScript 中保留多个表单值？

Question

下面是我尝试使用 JavaScript 保留表单值的方法，但它不起作用：

<form action="" method="Post" onload="saveData();">
<Label>1. What is your favourite browser?</Label>
<select id="browserValue">
    <option value="Internet Explorer">Internet Explorer</option>
    <option value="Firefox">Firefox</option>
    <option value="Chrome">Chrome</option>
    <option value="Opera">Opera</option>
    <option value="Safari">Safari</option>
</select>
<br>
<br>
<Label>2. What is your favourite food group?</Label>
<select id="foodValue">
    <option value="Meats/Alternatives">Meats/Alternatives</option>
    <option value="Vegetables">Vegetables</option>
    <option value="Dairy Products">Dairy Products</option>
    <option value="Fruits">Fruits</option>
    <option value="Grains">Grains</option>
    <option value="Confections (Junk Food)">Confections (Junk Food)</option>
</select>
<br>
<br>
<Label>3. What is your favourite game genre?</Label>
<select id="gameValue">

    <option value="FPS">First Person Shooter (Ex: Halo, Call of Duty)</option>
    <option value="TPS">Third Person Shooter (Ex: Ghost Recon, Gear of War)</option>
    <option value="Puzzle">Puzzle (Ex: Sudoku, Minesweeper)</option>
    <option value="Sim">Simulation (Ex: Minecraft, SimCity)</option>
    <option value="Other">Other (Please specify the genre)</option>
   </select>

<br>
<br>
<input type="button"  value="Submit">
</form>
<script>
function saveData(){
    var q1 = document.getElementById("browserValue").onChange().value;
    var a = localStorage.setItem("browsers", q1);
    var q2 = document.getElementById("foodValue").onChange().value;
    var b = localStorage.setItem("food", q2); 
    var q3 = document.getElementById("gameValue").onChange().value;
    var c = localStorage.setItem("game", q3);

   }
   document.getElementById("browserValue").value = a;
   document.getElementById("foodValue").value = b;
   document.getElementById("gameValue").value = c;  
</script>

Answer 1

我创建了一个 fiddle，它似乎可以正常工作： http://jsfiddle.net/4hsxjhnd/1/

HTML

<form action="" method="Post">
<Label>1. What is your favourite browser?</Label>
<select id="browserValue">
    <option value="Internet Explorer">Internet Explorer</option>
    <option value="Firefox">Firefox</option>
    <option value="Chrome">Chrome</option>
    <option value="Opera">Opera</option>
    <option value="Safari">Safari</option>
</select>
<br>
<br>
<Label>2. What is your favourite food group?</Label>
<select id="foodValue">
    <option value="Meats/Alternatives">Meats/Alternatives</option>
    <option value="Vegetables">Vegetables</option>
    <option value="Dairy Products">Dairy Products</option>
    <option value="Fruits">Fruits</option>
    <option value="Grains">Grains</option>
    <option value="Confections (Junk Food)">Confections (Junk Food)</option>
</select>
<br>
<br>
<Label>3. What is your favourite game genre?</Label>
<select id="gameValue">

    <option value="FPS">First Person Shooter (Ex: Halo, Call of Duty)</option>
    <option value="TPS">Third Person Shooter (Ex: Ghost Recon, Gear of War)</option>
    <option value="Puzzle">Puzzle (Ex: Sudoku, Minesweeper)</option>
    <option value="Sim">Simulation (Ex: Minecraft, SimCity)</option>
    <option value="Other">Other (Please specify the genre)</option>
   </select>

<br>
<br>
<input type="button" value="Submit" onclick="savecode()">
<input type="button" value="Reload" onclick="getcode()">
</form>

JS:

//Script
function savecode()
{
  localStorage.setItem("browsers", $("#browserValue").val());
  localStorage.setItem("food", $("#foodValue").val());
  localStorage.setItem("game", $("#gameValue").val());
}

function getcode()
{
    alert(localStorage.getItem("browsers"));
   document.getElementById("browserValue").value = localStorage.getItem("browsers");
   document.getElementById("foodValue").value = localStorage.getItem("food");
   document.getElementById("gameValue").value = localStorage.getItem("game");  
}

我在解决这个问题时学到的一些东西是：onload 只适用于 body see here

此外，我还读到了关于将 onchange 包装在 document ready 中或将事件侦听器附加到它以正确触发事件的信息： event listener, ready event

我稍微修改了程序。如果您按下重新加载，它将从本地存储中获取值，而不是在页面刷新时自动填充的值，这可以很容易地更改。另外，我使用的是提交按钮而不是 onchange。

希望对您有所帮助！

如何在重新加载网页后在 JavaScript 中保留多个表单值？

How to retain multiple form values in JavaScript after reloading a web page?

javascript

jquery

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javascript-objects

dom-events