我有一个用于html的jsp文件和一个用于Java的myservlet.java文件。我对于在jsp或Java中将在哪个文件中编写插入查询感到困惑？
什么是netbean的插入查询？是否正确？
字符串查询=“ INSERT INTO Teacher1（id，name）” +“ VALUES（” +1 +“，'” + aaa +“'）”;
myservlet.java
class dbconn {
Connection c1 = null;
Statement st = null;
ResultSet rs = null;
private final String ac;
private final String aaa;
dbconn() {
try {
Class.forName("com.mysql.jdbc.Driver");
c1 = DriverManager.getConnection("jdbc:mysql://localhost:3306/teacher", "root", "abcde");
} catch (Exception cnfe) {
System.out.println("Couldn't find the driver!");
System.out.println("Couldn't connect: print out a stack trace and exit.");
System.out.println("We got an exception while creating a statement:" + "that probably means we're no longer connected.");
}
try {
st = (Statement) c1.createStatement();
System.out.println("Statement Created Successfully");
} catch (SQLException se) {
System.out.println("We got an exception while creating a statement:" + "that probably means we're no longer connected.");
}
if (c1 != null) {
System.out.println("Hooray! We connected to the database!");
} else {
System.out.println("We should never get here.");
}
String query = "INSERT INTO teacher1 (id,name) "
+ "VALUES (" + 1 + ", '" + aaa + "')"; // insert query is this
}
protected void processRequest(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
try {
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet myservlet</title>");
out.println("</head>");
out.println("<body >");
out.println("<h1>Servlet myservlet at " + request.getContextPath() + "</h1>");
String name = request.getParameter("firstname");
out.println("<h2>" + name + "</h2>");
out.println("</body>");
out.println("</html>");
} finally {
out.close();
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
public String getServletInfo() {
return "Short description";
}
}
index.jsp
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page</title>
</head>
<body>
<h1>Hello World!</h1>
<form action="myservlet" method="GET" >
First name:<br>
<input type="text" name="firstname"/>
<br>
Last name:
<br>
<input type="text" name="lastname" />
<br> <br>
<input type="submit" value="Submit"/>
</form>
</body>
</html>
最佳答案
我认为您的代码不完整且非常复杂，因此这里很容易提供一种在数据库中插入值的方法：
public boolean insert(String firstname, String lastname) throws SQLException, ClassNotFoundException {
//Connection to database
Class.forName("com.mysql.jdbc.Driver");
Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/teacher", "root", "abcde");
boolean succes = false;
PreparedStatement statement = null;
try {
//Create a prepared statement
String requete = "INSERT INTO teacher1 (fname,lname) VALUES (?, ?)";
statement = connection.prepareStatement(requete);
statement.setString(1, firstname);
statement.setString(2, lastname);
//Excute the insertion
int r = statement.executeUpdate();
//Test the insertion is correct or no
if (r == 1) {
succes = true;
}
} catch (SQLException e) {
System.out.println("Exception :" + e);
} finally {
//Close your connection
if (statement != null) {
try {
statement.close();
} catch (SQLException ex) {
}
}
if (connection != null) {
try {
connection.close();
} catch (SQLException ex) {
}
}
}
return succes;
}
关于java - 如何从html文本框在mysql表中插入记录？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/38422884/