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58问答库 > Java 很简单的一个问题。在文本框里输入数据，想在一个方法里得到输入文本框的内容。但提示空指针错误

Java 很简单的一个问题。在文本框里输入数据，想在一个方法里得到输入文本框的内容。但提示空指针错误

2025-04-07 11:39:03

推荐回答（1个）

回答（1）：

把：
JTextField tf1 = new JTextField();
JTextField tf2 = new JTextField();
JTextField tf3 = new JTextField();
JTextField tf4 = new JTextField();
JTextField tf5 = new JTextField();
作为成员变量，提到 JButton b2=null; 后面。
建议阅读成员变量与局部变量的区别的相关知识

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