java - Java FX 输入字段的错误异常处理，确保该字段只接受正整数

Question

目前，如果字段为空，我的错误异常处理会返回错误 - 如何扩展它以包含所有非正整数的字符？

Button hdButton=new Button();
hdButton.setText("Save");
hdButton.setOnAction(e -> 
    {
        if(memoryField.getText().isEmpty())
        {
            dsdisplay2.setText("ERROR: You must enter a positive number in order to set the 
            memory\n");
        }
        else
        {
            s1.setHardDisk(Integer.parseInt(hardDisk.getText()));
            dsdisplay2.setText("The Hard Disk size for your PC has been set to: " + s1.getMemory());

        }

Answer 1

将 Integer.parseInt() 封装在 try block 中，并catch NumberFormatException。

try {
    int size = Integer.parseInt(hardDisk.getText());
    s1.setHardDisk(size);
    dsdisplay2.setText("The Hard Disk size for your PC has been set to: " + s1.getMemory());
} catch (NumberFormatException e) {
    dsdisplay2.setText("ERROR: You must enter a positive number in order to set the memory\n");
}

这样，您就不需要在设置 s1.setHardDisk 之前验证输入，因为如果输入格式错误，Integer.parseInt 将引发异常。