3

我尝试使用 javascript 传递值，如下所示

<script language= "javascript" type= "text/javascript">
var num;
function getVal()
{
num=document.getElementById('in').value;
alert(document.getElementById('parm').value);
}
</script>
<body>
<form >
Number : <input type="text" id="in"  ><br/>
<button id="myBtn" onclick="getVal()">Try it</button><br/>  
</form>
<APPLET code="Calc.class" width="100" height="100">
<PARAM name="number" id="parm">
</APPLET>

</body>    
</html>

警报框在屏幕上显示输入的值，但小程序代码显示的不同。我的小程序代码是

public class Calc extends Applet
{

    private String strDefault = "Hello! Java Applet.";
    public void paint(Graphics g) {
    String strParameter = this.getParameter("number");
    if (strParameter == null)
    strParameter = strDefault;
    g.drawString(strParameter, 10, 10);
    }
}

谁能告诉我将值传递到参数标签和从参数标签到html的代码？

4

2 回答 2

4

我认为您可以从 javascript 对象中指定参数，如下所示：

<applet code="Calc.class" width="100" height="100">
    <param name="number" id="parm" value="&{num};">
</applet>

但是，我不确定与 IE 的兼容性，因此您可能必须将document.write您的小程序代码注入相应的参数值，如下所示：

<head>
    <script type="text/javascript">
        var num;

        function getVal() {
            num = document.getElementById('in').value;

            writeAppletTags();
        }

        function writeAppletTags() { 
            var container = document.getElementById("applet-container");

            container.innerHTML = "<applet code=\"Calc.class\" width=\"100\" height=\"100\">";
            container.innerHTML += "<param name=\"number\" value=\"" + num + "\">";
            container.innerHTML += "</applet>";
        }
    </script> 
</head>
<body>
    Number : <input type="text" id="in"  ><br/>
    <button id="myBtn" onclick="getVal()">Try it</button><br/>  
    <div id="applet-container" />
</body>

从 Java 发送 POST

正如我在评论中所说，这有点复杂。您必须将您的值发布（也可以使用 GET）到托管文件（可以是任何服务器端脚本技术）。下面演示了这一点，代码取自此处。

URL url;
URLConnection urlConnection;
DataOutputStream outStream;
DataInputStream inStream;

// Build request body
String body = "key=value";

// Create connection
url = new URL("http://myhostedurl.com/receiving-page.php");
urlConnection = url.openConnection();
((HttpURLConnection)urlConnection).setRequestMethod("POST");
urlConnection.setDoInput(true);
urlConnection.setDoOutput(true);
urlConnection.setUseCaches(false);
urlConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
urlConnection.setRequestProperty("Content-Length", ""+ body.length());

// Create I/O streams
outStream = new DataOutputStream(urlConnection.getOutputStream());
inStream = new DataInputStream(urlConnection.getInputStream());

// Send request
outStream.writeBytes(body);
outStream.flush();
outStream.close();

// Close I/O streams
inStream.close();
outStream.close();
于 2012-09-25T14:32:33.247 回答
4

本文来源

例如：这是您的小程序代码：

import java.applet.*;    
import java.awt.*; 

public class DrawStringApplet extends Applet {

  private String defaultMessage = "Hello!";

  public void paint(Graphics g) {

    String inputFromPage = this.getParameter("Message");
    if (inputFromPage == null) inputFromPage = defaultMessage;
    g.drawString(inputFromPage, 50, 25);

  }

}

然后在 HTML 中：

<HTML>
<HEAD>
<TITLE> Draw String </TITLE>
</HEAD>

<BODY>
This is the applet:<P>
<APPLET code="DrawStringApplet" width="300" height="50">
<PARAM name="Message" value="Howdy, there!">
This page will be very boring if your 
browser doesn't understand Java.
</APPLET>
</BODY>
</HTML>

注意： DrawStringApplet 是你的小程序名称；Message是发送给小程序的参数；然后小程序将显示：Howdy, there! 结果。

于 2012-09-25T14:34:48.030 回答