void button1_actionPerformed(ActionEvent e) {
String t1=textField1.getText().trim();
String t2=textField2.getText().trim();
String t3=textField3.getText().trim();
String t4=textField4.getText().trim(); if(t1==null && t2==null&& t3==null&& t4==null)
{
}
}
String t1=textField1.getText().trim();
String t2=textField2.getText().trim();
String t3=textField3.getText().trim();
String t4=textField4.getText().trim(); if(t1==null && t2==null&& t3==null&& t4==null)
{
}
}
import java.awt.event.*;
import javax.swing.*;
import com.borland.jbcl.layout.*;
import java.sql.*;public class AddRowFrame extends JFrame {
Connection con;
String url = "jdbc:odbc:Xu";
ResultSet rs;
private JPanel contentPane;
private XYLayout xYLayout1 = new XYLayout();
private TextField textField1 = new TextField();
private TextField textField2 = new TextField();
private TextField textField3 = new TextField();
private TextField textField4 = new TextField();
private Label label1 = new Label();
private Label label2 = new Label();
private Label label3 = new Label();
private Label label4 = new Label();
private Button button1 = new Button();
private Button button2 = new Button(); //Construct the frame
public AddRowFrame() {
DBConnect(url);
enableEvents(AWTEvent.WINDOW_EVENT_MASK);
try {
jbInit();
}
catch(Exception e) {
e.printStackTrace();
}
}
//Component initialization
private void jbInit() throws Exception {
//setIconImage(Toolkit.getDefaultToolkit().createImage(AddRowFrame.class.getResource("[Your Icon]")));
contentPane = (JPanel) this.getContentPane();
textField1.setText(" ");
contentPane.setLayout(xYLayout1);
this.setSize(new Dimension(400, 300));
this.setTitle("Frame Title");
textField2.setText(" ");
textField3.setText(" ");
textField4.setText(" ");
label1.setText("姓名");
label2.setText("年龄");
label3.setText("地址");
label4.setText("密码");
button1.setLabel("添 加");
button1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(ActionEvent e) {
button1_actionPerformed(e);
}
});
button2.setLabel("取 消");
button2.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(ActionEvent e) {
button2_actionPerformed(e);
}
});
contentPane.add(textField3, new XYConstraints(158, 151, -1, -1));
contentPane.add(textField2, new XYConstraints(159, 92, -1, -1));
contentPane.add(textField1, new XYConstraints(159, 41, -1, -1));
contentPane.add(textField4, new XYConstraints(158, 205, -1, -1));
contentPane.add(label1, new XYConstraints(104, 42, -1, -1));
contentPane.add(label2, new XYConstraints(104, 94, -1, -1));
contentPane.add(label3, new XYConstraints(103, 153, -1, -1));
contentPane.add(label4, new XYConstraints(104, 206, -1, -1));
contentPane.add(button1, new XYConstraints(20, 234, -1, -1));
contentPane.add(button2, new XYConstraints(287, 235, -1, -1));
}
//Overridden so we can exit when window is closed
protected void processWindowEvent(WindowEvent e) {
super.processWindowEvent(e);
if (e.getID() == WindowEvent.WINDOW_CLOSING) {
System.exit(0);
}
} void button2_actionPerformed(ActionEvent e) {
super.setVisible(false);
}
void DBConnect(String url){
try {
String driver ="sun.jdbc.odbc.JdbcOdbcDriver";
Class.forName(driver);
con =DriverManager.getConnection (url, "", "");
}catch (SQLException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
} void DBClose(){
try{
con.close();
}catch(SQLException e)
{
}
}
ResultSet queryDB(String qry){
ResultSet rs=null; try{
Statement stmt= con.createStatement (); rs= stmt.executeQuery(qry); //System.out.println("EXECUTED QUERY ---> " + qry);
}catch(SQLException e2){
}
return rs;
} void button1_actionPerformed(ActionEvent e) {
String t1=textField1.getText().trim();
String t2=textField2.getText().trim();
String t3=textField3.getText().trim();
String t4=textField4.getText().trim(); if(t1==null && t2==null&& t3==null&& t4==null)
{
System.out.println("in");
}
}
}
String t1=textField1.getText().trim();
String t2=textField2.getText().trim();
String t3=textField3.getText().trim();
String t4=textField4.getText().trim(); if(t1.equals("") && t2.equals("") && t3.equals("") && t4.equals(""))
{
}
}
String t1=textField1.getText().trim();
String t2=textField2.getText().trim();
String t3=textField3.getText().trim();
String t4=textField4.getText().trim(); if(t1.equals("") && t2.equals("") && t3.equals("") && t4.equals(""))
{
}
}if(t1==null && t2==null&& t3==null&& t4==null) 都可以!
你写的是或的关系!
String t1=textField1.getText().trim();
String t2=textField2.getText().trim();
String t3=textField3.getText().trim();
String t4=textField4.getText().trim(); if(t1.length() == 0 && t2.length() == 0 && t3.length() == 0 && t4.length() == 0 )
{
}
}
我刚改了名字,新名字怎么样?
t1.equals("") && t2.equals("") && t3.equals("") && t4.equals("")
同意忽忽
用equal顺便问一下.trim()是什么方法?
{
//值为空
//记住要把text == null放在text.equals("")前边。虽然这种情况可能性较小。
}