Implementation of interactive use of JSP data and JavaScript data

For Web applications, front-end (JavaScript) and back-end (Jsp/servlet) are not able to share data, only the back-end program (JSP) to output data, generate pages to the front, The JavaScript code in the generated page is likely to get the so-called JSP data. In the same way, the JavaScript data can be obtained from the JSP program only if the data in JavaScript is submitted to the back-end JSP code.

How do you implement data from a JSP in a page's JavaScript or use a page's JavaScript data in a JSP?

One, the page of JavaScript data How to submit to the background of the JSP program

① can pass JavaScript data to the JSP program as a xxx.jsp?var1=aaa&var2=bbb parameter in the form of a URL, in the JSP

<%String strVar1=request.getParameter("var1");%>

You can get the data that the JavaScript script passes over;

② uses JavaScript to pass data to a JSP program by adding hidden field information to the form, and then submitting the form.

Refer to the following script:

<script language="JavaScript">
<!--
/***************************************************************
* JavaScript脚本，放置在页面中的任何位置都可以
* insertclick()函数获取JSP传递到页面中的变量varMC，
* 然后就可以在JavaScript中修改这个变量的值，再通过
* post的方式提交给JSP程序来使用。
***************************************************************/
function insertclick(){
var1 = document.all.mc.value; //获取页面form中的变量值
var1 = var1 + "名称";
document.insertForm.submit();
}
//-->
</script>
<!-- html页面form表单，放置在html页面中的位置不限 -->
<form name="insertForm" method="post" action="yourJSP">
<!-- 下面这一句是获取JSP程序中传递过来的变量值 -->
<input type="hidden" name="mc" value="<%=varMC%>">
<input type="button" value="提交" onclick="insertclick()">
</form>

Second, the page of JavaScript data How to use the background of the JSP program data

This is simpler and can be used directly in JavaScript scripts to pass data from a JSP program to a JavaScript script.

Refer to the following script:

<!-- html页面form表单，放置在html页面中的位置不限 -->
<form name="insertForm" method="post" action="yourJSP">
<input type="hidden" name="mc" value="">
</form>
<script language="JavaScript">
<!--
/***************************************************************
* JavaScript脚本，放置在页面中form以后的任何位置都可以
* 使用JavaScirpt获取JSP传递到页面中的变量varMC，
* 然后就可以在JavaScript中使用这个变量的值，通过
* JavaScript脚本赋值给form中的隐藏域。
***************************************************************/
var1 = "<%=varMC%>"; //获取JSP中的变量值
document.all.mc.value = var1;
//-->
</script>