<body>
<form action="javascript:void(0);" method="POST" onsubmit="app.Add()">
<input type="text" id="add-name" placeholder="New country ">
<input type="number" id="add-popu" placeholder="New population">
<input type="submit" value="Add">
</form>
<div id="spoiler" role="aria-hidden">
<form action="javascript:void(0);" method="POST" id="saveEdit">
<input type="text" id="edit-name">
<input type="text" id="edit-popu">
<input type="submit" value="Ok" /> <a onclick="CloseInput()" aria-label="Close">✖</a>
</form>
</div>
<p id="counter"></p>
<table>
<tr>
<th>Country</th>
<th>Population</th>
</tr>
<tbody id="countries"></tbody>
<tbody id="popultns"></tbody>
</table>
<script type="text/javascript" src="main.js"></script>
<script>
var app = new function()
{ this.el = document.getElementById('countries');
this.el = document.getElementById('popultns');
let loadTableData = data2;
this.Count = function(data)
{ var el = document.getElementById('counter');
var name = 'country2';
var pop = 'popu2'
if (data)
{ if (data > 1)
{ name = 'countries' ;
pop = "popultns" ;
}
el.innerHTML = data + ' ' + name + ' ' + pop ;
}
else
{ el.innerHTML = 'No ' + name + ' ' + pop ; }
};
this.FetchAll = function()
{ var data = '';
if (loadTableData.length > 0)
{ for (i = 0; i < loadTableData.length; i++)
{ data += '<tr>';
data += '<td>' + loadTableData[i].country + '</td>';
data += '<td>' + loadTableData[i].population + '</td>';
data += '<td><button onclick="app.Edit(' + i + ')">Edit</button></td>';
data += '<td><button onclick="app.Delete(' + i + ')">Delete</button></td>';
data += '</tr>';
}
}
this.Count(loadTableData.length);
return this.el.innerHTML = data;
};
this.Add = function ()
{ el = document.getElementById('add-name');
el2 = document.getElementById('add-popu');
// Get the value
var country2 = el.value;
var pop = el2.value;
if (country2)
{ // Add the new value
loadTableData.push(country2.trim() );
// Reset input value
el.value = '';
//el2.value = '';
// Dislay the new list
this.FetchAll();
}
};
the image is the ui tht im working for the function
我应该基于可从我的main.js脚本（JSon格式）中获得的数据自动生成表。数据加载没有问题，因为数据可以显示在我的html文件中。但是，问题出在我单击“添加”按钮以更新表中的数据时，我的数据在自动生成的表上未定义返回时。当我单击编辑按钮时，数据将正确获取。只有在显示时，它才返回给我未定义的信息。
最佳答案
我知道怎么了。
在这里，我附上我完成的数据的代码和示例。
希望这会对像我这样在undrsntdng CRUD中遇到麻烦的应届毕业生有所帮助
<html>
<head>
<meta charset="UTF-8">
<title>Countries CRUD</title>
<style>
input[type='submit'], button, [aria-label]{
cursor: pointer;
}
#spoiler{
display: none;
}
</style>
</head>
<body>
<form action="javascript:void(0);" method="POST" onsubmit="app.Add()">
<input type="text" id="add-name" placeholder="New country ">
<input type="number" id="add-popu" placeholder="New population">
<input type="submit" value="Add">
</form>
<div id="spoiler" role="aria-hidden">
<form action="javascript:void(0);" method="POST" id="saveEdit">
<input type="text" id="edit-name">
<input type="text" id="edit-popu">
<input type="submit" value="Ok" /> <a onclick="CloseInput()" aria-label="Close">✖</a>
</form>
</div>
<p id="counter"></p>
<table>
<tr>
<th>Country</th>
<th>Population</th>
</tr>
<tbody id="countries"></tbody>
<tbody id="popultns"></tbody>
</table>
<script type="text/javascript" src="main.js"></script>
<script>
var app = new function()
{ this.el = document.getElementById('countries' && 'popultns');
//this.el = document.getElementById('popultns');
let loadTableData = data2;
this.Count = function(data)
{ var el = document.getElementById('counter');
var name = 'country2';
var pop = 'popu2'
if (data)
{ if (data > 1)
{ name = 'countries' ;
pop = "populations" ;
}
el.innerHTML = data + ' ' + name + ' ' + pop ;
}
else
{ el.innerHTML = 'No ' + name + ' ' + pop ; }
};
this.FetchAll = function()
{ var data = '';
if (loadTableData.length > 0)
{ for (i = 0; i < loadTableData.length; i++)
{ data += '<tr>';
data += '<td>' + loadTableData[i].country + '</td>';
data += '<td>' + loadTableData[i].population + '</td>';
data += '<td><button onclick="app.Edit(' + i + ')">Edit</button></td>';
data += '<td><button onclick="app.Delete(' + i + ')">Delete</button></td>';
data += '</tr>';
}
}
this.Count(loadTableData.length);
return this.el.innerHTML = data;
};
this.Add = function ()
{ el = document.getElementById('add-name');
el2 = document.getElementById('add-popu');
// Get the value
var country2 = el.value;
var popltn = el2.value;
if (country2 && popltn )
{ // Add the new value
//loadTableData.push(country2.trim() );
loadTableData.push({country: country2, population:popltn});
// Reset input value
el.value = '';
el2.value = '';
// Dislay the new list
this.FetchAll();
}
};
this.Edit = function (item)
{ var el3 = document.getElementById('edit-name');
var el4 = document.getElementById('edit-popu');
// Display value in the field
let index = item;
el3.value = loadTableData[index].country;
el4.value = loadTableData[index].population;
// Display fields
document.getElementById('spoiler').style.display = 'block';
self = this;
document.getElementById('saveEdit').onsubmit = function()
{
// Get value
var country2 = el3.value;
var popltn = el4.value;
//console.log({country2, pop});
if (country2 || pop)
//console.log(country2);
{ // Edit value (strt,del,replace)
console.log(country2,popltn);
console.log(index, 1,({country2,popltn}));
//update array
loadTableData[index].country = el3.value;
loadTableData[index].population = el4.value;
//self.loadTableData.splice(index, 1,({country2,popltn}));
//console.log(index, 1, pop.trim());
//self.loadTableData.splice(index, 1, pop.trim());
// Display the new list
self.FetchAll();
// Hide fields
CloseInput();
}
}
};
this.Delete = function (item)
{
// Delete the current row
loadTableData.splice(item, 1);
// Display the new list
this.FetchAll();
};
}
app.FetchAll();
function CloseInput()
{ document.getElementById('spoiler').style.display = 'none';}
</script>
</body>
</html>