我如何将条目从HTML5 FormData对象转换为JSON?
解决方案不应该使用jQuery。而且，它不应该简单地序列化整个FormData对象，而应该只序列化它的键/值条目。
当前回答
如果需要支持序列化嵌套字段(类似于PHP处理表单字段的方式)，可以使用以下函数
function update(data, keys, value) { if (keys.length === 0) { // Leaf node return value; } let key = keys.shift(); if (!key) { data = data || []; if (Array.isArray(data)) { key = data.length; } } // Try converting key to a numeric value let index = +key; if (!isNaN(index)) { // We have a numeric index, make data a numeric array // This will not work if this is a associative array // with numeric keys data = data || []; key = index; } // If none of the above matched, we have an associative array data = data || {}; let val = update(data[key], keys, value); data[key] = val; return data; } function serializeForm(form) { return Array.from((new FormData(form)).entries()) .reduce((data, [field, value]) => { let [_, prefix, keys] = field.match(/^([^\[]+)((?:\[[^\]]*\])*)/); if (keys) { keys = Array.from(keys.matchAll(/\[([^\]]*)\]/g), m => m[1]); value = update(data[prefix], keys, value); } data[prefix] = value; return data; }, {}); } document.getElementById('output').textContent = JSON.stringify(serializeForm(document.getElementById('form')), null, 2); <form id="form"> <input name="field1" value="Field 1"> <input name="field2[]" value="Field 21"> <input name="field2[]" value="Field 22"> <input name="field3[a]" value="Field 3a"> <input name="field3[b]" value="Field 3b"> <input name="field3[c]" value="Field 3c"> <input name="field4[x][a]" value="Field xa"> <input name="field4[x][b]" value="Field xb"> <input name="field4[x][c]" value="Field xc"> <input name="field4[y][a]" value="Field ya"> <input name="field5[z][0]" value="Field z0"> <input name="field5[z][]" value="Field z1"> <input name="field6.z" value="Field 6Z0"> <input name="field6.z" value="Field 6Z1"> </form> <h2>Output</h2> <pre id="output"> </pre>
其他回答
可以通过使用FormData()对象来实现这一点。这个FormData对象将使用表单的当前键/值填充表单，使用每个元素的name属性填充键，使用它们提交的值填充值。它还将对文件输入内容进行编码。
例子:
var myForm = document.getElementById('myForm');
myForm.addEventListener('submit', function(event)
{
event.preventDefault();
var formData = new FormData(myForm),
result = {};
for (var entry of formData.entries())
{
result[entry[0]] = entry[1];
}
result = JSON.stringify(result)
console.log(result);
});
为我工作
var myForm = document.getElementById("form");
var formData = new FormData(myForm),
obj = {};
for (var entry of formData.entries()){
obj[entry[0]] = entry[1];
}
console.log(obj);
这解决了我的问题，这是一个对象
const formDataObject = (formData) => {
for (const key in formData) {
if (formData[key].startsWith('{') || formData[key].startsWith('[')) {
try {
formData[key] = JSON.parse(formData[key]);
console.log("key is :", key, "form data is :", formData[key]);
} catch (error) {
console.log("error :", key);
}
}
}
console.log("object", formData)
}
另一种适用于选择多个或具有相同name属性的输入的方法:
function form_to_json() { const form_data = new FormData(document.querySelector('form')) const uniqueKeys = [...new Set(form_data.keys())] const obj = {} uniqueKeys.forEach((value, key) => { obj[value] = (form_data.getAll(value).length > 1) ? form_data.getAll(value) : form_data.get(value) }) const json = JSON.stringify(obj) alert(json) } <form> <input type="text" name="name" value="Cesar"></br> <select name="cars" id="cars" multiple> <option value="volvo" selected>Volvo</option> <option value="saab" selected>Saab</option> </select> <input type="button" onclick="form_to_json()" value="Ok"> </form>
我知道已经很晚了，但这是解决方案;
new URLSearchParams(new FormData(formElement)).toString()
这个可以作为正文发送。遗憾的是，它不是JSON。
