//我在使用 Netbeans 时遇到问题。当我单击“注册”时，我试图将注册表中输入的值转到 SQL 表，但什么也没有发生。有人可以帮忙吗？
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package networking;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.Statement;
/**
*
* @author user
*/
public class Registration extends javax.swing.JFrame {
/**
* Creates new form Registration
*/
public Registration() {
initComponents();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jLabel1 = new javax.swing.JLabel();
jLabel2 = new javax.swing.JLabel();
jLabel3 = new javax.swing.JLabel();
jLabel4 = new javax.swing.JLabel();
jLabel5 = new javax.swing.JLabel();
jLabel6 = new javax.swing.JLabel();
FullNameField = new javax.swing.JTextField();
EmailField = new javax.swing.JTextField();
Username = new javax.swing.JTextField();
jScrollPane1 = new javax.swing.JScrollPane();
AdressField = new javax.swing.JTextArea();
PasswordField = new javax.swing.JPasswordField();
Registeration = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jLabel1.setText("Registration Form ");
jLabel2.setText("Full Name");
jLabel3.setText("Email");
jLabel4.setText("Username");
jLabel5.setText("Password");
jLabel6.setText("Adresse");
FullNameField.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
FullNameFieldActionPerformed(evt);
}
});
AdressField.setColumns(20);
AdressField.setRows(5);
jScrollPane1.setViewportView(AdressField);
Registeration.setText("Register");
Registeration.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
RegisterationActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(105, 105, 105)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
.addComponent(Registeration)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jLabel2, javax.swing.GroupLayout.PREFERRED_SIZE, 64, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
.addComponent(jLabel3, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(jLabel4, javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jLabel5, javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jLabel6, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)))
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(PasswordField)
.addComponent(Username)
.addComponent(EmailField)
.addComponent(FullNameField)
.addComponent(jScrollPane1)))))
.addGroup(layout.createSequentialGroup()
.addGap(21, 21, 21)
.addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 131, javax.swing.GroupLayout.PREFERRED_SIZE)))
.addGap(105, 282, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(26, 26, 26)
.addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 29, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(28, 28, 28)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel2)
.addComponent(FullNameField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel3)
.addComponent(EmailField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jLabel4)
.addComponent(Username, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel5)
.addComponent(PasswordField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGroup(layout.createSequentialGroup()
.addGap(20, 20, 20)
.addComponent(jLabel6)))
.addGap(18, 18, 18)
.addComponent(Registeration)
.addContainerGap(27, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void RegisterationActionPerformed(java.awt.event.ActionEvent evt) {
try{
Connection con = DriverManager.getConnection("jdbc:mysql://localhost/networks","root","mamaendbaba");
Statement stat = (Statement) con.createStatement();
String Name = FullNameField.getText();
String UserName= Username.getText();
String Adr = AdressField.getText();
String Pass = PasswordField.getText();
String Emai = EmailField.getText();
String excmd = "INSERT INTO networks registerd(Name, UserName, Address, Password, Email)" +
" VALUES (?, ?, ?, ?, ?)";
@SuppressWarnings("UnusedAssignment")
PreparedStatement statement =con.prepareStatement(excmd);
statement = (PreparedStatement) con.createStatement();
// get field values ...
statement.setString(1, Name);
statement.setString(2, UserName);
statement.setString(3, Adr);
statement.setString(4, Pass);
statement.setString(5, Emai);
statement.executeUpdate();
}
catch(Exception e)
{
}
}
private void FullNameFieldActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(Registration.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(Registration.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(Registration.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(Registration.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new Registration().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JTextArea AdressField;
private javax.swing.JTextField EmailField;
private javax.swing.JTextField FullNameField;
private javax.swing.JPasswordField PasswordField;
private javax.swing.JButton Registeration;
private javax.swing.JTextField Username;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JLabel jLabel3;
private javax.swing.JLabel jLabel4;
private javax.swing.JLabel jLabel5;
private javax.swing.JLabel jLabel6;
private javax.swing.JScrollPane jScrollPane1;
// End of variables declaration
}
这是完整的代码，不需要任何解释，basiclu 它是一个用于注册的 jform，只需看看可以做什么，这样你就可以看到我正在从表单中获取值并尝试将它们插入表中，怎么不管用..
最佳答案
您的 SQL 参数变量中缺少多个单引号:
String excmd = "INSERT INTO networks registerd VALUES ('" + Name + "','"+ UserName +"','"+ Adr +"','"+ Pass +"','"+ Emai +"')";
此外，您没有在异常 block 中显示任何内容，这会使代码无声地失败。您可以添加:
e.printStackTrace();
更好用PreparedStatement在这里，因为它不仅消除了提供这些报价的需要，而且还可以防止 SQL Injection攻击。
<小时/>另一个潜在的错误来源是列顺序可能不完全匹配，例如可能有一个自动增量列，这意味着您必须在 SQL 中指定列名称。您也可以省略数据库名称，例如:
String excmd =
"INSERT INTO registerd(Name, UserName, Address, Password, Email)" +
" VALUES (?, ?, ?, ?, ?)";
PreparedStatement statement = con.createPreparedStatement(excmd);
// get field values ...
statement.setString(1, Name);
statement.setString(2, UserName);
statement.setString(3, Adr);
statement.setString(4, Pass);
statement.setString(5, Emai);
statement.executeUpdate();
关于java - Netbeans GUI 和 SQL 问题，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/14087314/