冗长的下载数据为CSV文件冗长、文件、数据、CSV
我需要下载在视图中为CSV文件显示表的内容。我有code正确格式化表的内容，以便它可以被存储为.csv文件（例如，列分隔符是逗号，表中的每个记录是一个新行）。
I need to download the contents of a table shown in the view as a CSV file. I have code to format the contents of the table properly so that it can be stored as a .csv file (for example, the column separator is a comma, each record of the table is in a new line).
所以，在我的控制器，我有以下的code：
So, in my controller, I have the following code:
window.location.href = '/download?data=' + encodeURIComponent($scope.csvString);
我使用了的NodeJS服务器部分。在这里，我有以下途径处理：
I am using NodeJs for the server part. Here, I have the following route handler:
app.get('/download', function (req, res) {
var data = req.query.data;
res.attachment('data.csv');
res.setHeader('Content-Type', 'text/csv');
res.end(data);
});
这工作完全正常。下载作品和数据下载的文件是在完美的CSV格式。没有问题。
This works perfectly fine. The download works and the data in the file downloaded is in perfect CSV format. No issues.
当有表中的记录太多的问题出现了，那就是当数据是巨大的。由于这个原因，查询参数确实是巨大的，我认为它超过了极限，因此，GET请求以400（错误请求）返回错误 - 请注意，根据我的分析，请求不会到达服务器，而不是我观察该请求使用Chrome开发者工具失败。在浏览器中，URL根本 www.my_domain.com/download?data=the_lengthy_data 。而已。该网页是空白/空的，没有文件被下载。
The issue arises when there are too many records in the table, that is when the data is huge. Due to this, the query parameter is really huge and I assume that it exceeds the limit and thus, the GET request returns with a 400 (Bad Request) error - note that according to my analysis, the request never reaches the server, instead I observed that the request failed using the Chrome Developer Tools. In the browser, the URL simply is www.my_domain.com/download?data=the_lengthy_data. That's it. The web page is blank / empty and no file is downloaded.
因此，我想知道我怎么可以下载冗长的数据？我碰到所有的例子做一个GET请求，因此我必须要通过冗长的数据作为查询参数。有一些其他的方法呢？
Thus, I wish to know how I can download the lengthy data? All examples that I came across do a GET request and thus I have to pass the lengthy data as a query parameter. Is there some other approach?
推荐答案
不是一个真正的回答你的问题，但是从外观上来看，你试图力在客户端上产生的数据的下载。那么在这种情况下，你可以创建一个数据的URI，直接在它的数据。
Not really an answer to your question, but from the looks of it, you are trying to "force" a download of data generated on the client. Then in this case, you could create a data URI, that has the data directly in it.
您的角度JS模板：
<a href="data:base64,{{btoa(csvString)}}" download>Download CSV</a>
您控制器：
$scope.btoa = function (val) {
return btoa(val);
};
这样一来，你的DOM应该是这样的：
As a result, your DOM should look like:
<!-- The link contains data to the CSV string "a,b,c" -->
<a href="data:text/csv;base64,YSxiLGM=" download>Download CSV</a>
和点击链接下载CSV文件。
And clicking the link downloads the CSV file.
修改
您也可以强制使用一种称为库字符串的下载 FileSaver.js 。
You could also force download of strings using a library called FileSaver.js.
所以像往常一样，你会得到CSV，但这个时候，你会将它转换为BLOB。
So as usual, you would get the CSV, but this time, you would convert it to a BLOB.
var csvBlob = new Blob([$scope.csvString], { type: 'text/csv;charset=utf-8' });
然后，你可以调用FileSaver.js的saveAs 功能。
saveAs(csvBlob, 'mydata.csv');
