Java 如果组件是 jlabel，则获取文本
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Get text if component is jlabel
提问by geo
I have a LayeredPane2 with mant components such as jlabels, jbutton etc. I want to loop in the components and if the component is a Jlabel, get it's text. How can I do this? Here is my code so far:
我有一个带有 jlabels、jbutton 等 mant 组件的 LayeredPane2。我想在组件中循环，如果组件是 Jlabel，则获取它的文本。我怎样才能做到这一点？到目前为止，这是我的代码：
//search the components
for (int j=0; j<jLayeredPane2.getComponents().length; j++){
//if it is a jlabel
if ("class javax.swing.JLabel".equals(jLayeredPane2.getComponent(j).getClass().toString())){
//HOW DO I GET THE LABEL TEXT??
}
}
采纳答案by Michael Berry
You want the instanceofkeyword, then a cast:
您需要instanceof关键字，然后是演员表：
if(jLayeredPane2.getComponent(j) instanceof JLabel) {
JLabel label = (JLabel)jLayeredPane2.getComponent(j);
String text = label.getText();
//...Then do whatever you want to do with said text.
}
回答by Bruno Toffolo
According to the JLabel docs, you can use the getText()method to retrieve the label text.
根据JLabel docs，您可以使用该getText()方法来检索标签文本。
String labelText = ((JLabel) jLayeredPane2.getComponent(j)).getText();
To check if the component is a JLabel you can use the comparison
要检查组件是否是 JLabel，您可以使用比较
if (jLayeredPane2.getComponent(j) instanceof JLabel) { }
as was already suggested in this question.
正如在这个问题中已经提出的那样。
Your final code would be something like this:
您的最终代码将是这样的：
if (jLayeredPane2.getComponent(j) instanceof JLabel) {
Label label = (JLabel) jLayeredPane2.getComponent(j);
String labelText = label.getText();
}
