Question

这不是我的代码。我的问题是，如何在html标签中显示'+ result +'之类的内容，以及在post响应中输入文本框的值中，它是如何有效的？... 另外，在旁注中，为什么当我执行response.write（form），然后是response.end（）作为response.end（form）的替代，代码停止工作。我是节点的新手，所以请把它弄清楚。

    // Load the http module to create an http server.
    var http = require('http'); 

    // Create a function to handle every HTTP request
    function handler(req, res){

  var form = '';

  if(req.method == "GET"){ 

    form = '<!doctype html> \
    <html lang="en"> \
    <head> \
    <meta charset="UTF-8">  \
    <title>Form Calculator Add Example</title> \
    </head> \
    <body> \
  <form name="myForm" action="/" method="post">\
      <input type="text" name="A"> + \
      <input type="text" name="B"> = \
      <span id="result"></span> \
      <br> \
      <input type="submit" value="Submit"> \
     </form> \
     </body> \
    </html>';

  //respond
  res.setHeader('Content-Type', 'text/html');
  res.writeHead(200);
  res.end(form);

  } else if(req.method == 'POST'){

    //read form data
    req.on('data', function(chunk) {

      //grab form data as string
      var formdata = chunk.toString();
    console.log(formdata);
      //grab A and B values
    console.log(formdata.split("&")[0]);
      var a = eval(formdata.split("&")[0]);
    console.log(a);
      var b = eval(formdata.split("&")[1]);

      var result = calc(a,b);

      //console.log(chunk.toString());
      //console.log(a);
      //console.log(b);
      //console.log(result);

      //fill in the result and form values
    form = '<!doctype html> \
    <html lang="en"> \
    <head> \
    <meta charset="UTF-8">  \
    <title>Form Calculator Add Example</title> \
    </head> \
    <body> \
   <form name="myForm" action="/" method="post">\
      <input type="text" name="A" value="'+a+'"> + \
      <input type="text" name="B" value="'+b+'"> = \
      <span id="result">'+result+'</span> \
      <br> \
      <input type="submit" value="Submit"> \
    </form> \
    </body> \
    </html>';

    //respond
    res.setHeader('Content-Type', 'text/html');
    res.writeHead(200);
    res.end(form);

    });

    } else {
    res.writeHead(200);
    res.end();
    };

    };

    //js functions running only in Node.JS
    function calc(a,b){
    return  Number(a)+Number(b);;
    }

    http.createServer(handler).listen(8080, function(err){
  if(err){
    console.log('Error starting http server');
  } else {
    console.log("Server running at http://127.0.0.1:8080/");          
    };
    });

我们如何在节点环境中使用HTML标记内的变量？

0 个答案: