问题描述
我有一个JTexTField
,我希望用户输入一个人的名字.我已经知道该名称应包含[a-zA-Z]
,.
和space
示例 Mr. Bill
.我正在使用DocumentFilter
来验证用户输入.但是,我不知道如何在DocumentFilter
中进行设置.
I have a JTexTField
that I would want a user to enter the name of a person. I have figured that the name should contain [a-zA-Z]
,.
and space
example Mr. Bill
. I am using a DocumentFilter
to validate user input.However, I cannot figure out how should I set this within my DocumentFilter
.
问题:我应该如何修改过滤器以实现上述行为?
Question: How should I modify my filter to achieve the above behavior?
关于如何验证人名的任何建议都被接受.
这是我的DocumentFilter:
Here is my DocumentFilter:
public class NameValidator extends DocumentFilter{
@Override
public void insertString(DocumentFilter.FilterBypass fp, int offset,
String string, AttributeSet aset) throws BadLocationException {
int len = string.length();
boolean isValidInteger = true;
for (int i = 0; i < len; i++) {
if (!Character.isLetter(string.charAt(i))) {
isValidInteger = false;
break;
}
}
if (isValidInteger)
super.insertString(fp, offset, string, aset);
else {
JOptionPane.showMessageDialog(null,
"Please Valid Letters only.", "Invalid Input : ",
JOptionPane.ERROR_MESSAGE);
Toolkit.getDefaultToolkit().beep();
}
}
@Override
public void replace(DocumentFilter.FilterBypass fp, int offset, int length,
String string, AttributeSet aset) throws BadLocationException {
int len = string.length();
boolean isValidInteger = true;
for (int i = 0; i < len; i++) {
if (!Character.isLetter(string.charAt(i)) ) {
isValidInteger = false;
break;
}
}
if (isValidInteger)
super.replace(fp, offset, length, string, aset);
else {
JOptionPane.showMessageDialog(null,
"Please Valid Letters only.", "Invalid Input : ",
JOptionPane.ERROR_MESSAGE);
Toolkit.getDefaultToolkit().beep();
}
}
}
这是我的考试班:
public class NameTest {
private JFrame frame;
public NameTest() {
frame = new JFrame();
initGui();
}
private void initGui() {
frame.setSize(100, 100);
frame.setVisible(true);
frame.setLayout(new GridLayout(2, 1, 5, 5));
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JTextField name = new JTextField(15);
((AbstractDocument) name.getDocument())
.setDocumentFilter(new NameValidator());
frame.add(name);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
NameTest nt = new NameTest();
}
});
}
}
推荐答案
您可以将JFormattedTextField
与MaskFormatter
结合使用. MaskFormatter
允许您指定有效字符的String
.
You could use a JFormattedTextField
with a MaskFormatter
. The MaskFormatter
allows you to specify a String
of valid characters.
MaskFormatter mf = new MaskFormatter( "***************" );
mf.setValidCharacters(" .abcABC");
JFormattedTextField ftf = new JFormattedTextField( mf );
在后台,格式化的文本字段使用DocumentFilter.阅读Swing教程中如何使用带格式的文本字段有关更多信息和示例.
Behind the scenes the formatted text field uses a DocumentFilter. Read the section from the Swing tutorial on How to Use Formatted Text Fields for more information and examples.
您也可以尝试在论坛/网站上搜索正则表达式DocumentFilter.这种类型的过滤器通常是可重用的,因为您只需要指定regex表达式即可.例如:在JTextField的DocumentFilter中使用正则表达式遇到问题
You can also try searching the forum/web for a regex DocumentFilter. This type of filter is generally reusable because you just need to specify the regex expression. For example: Trouble using regex in DocumentFilter for JTextField
这篇关于使用DocumentFilter过滤JTextField的字符串,空格和点(.)的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!