java.lang.NumberFormatException：对于输入字符串：“” javafx

Question

public void calculer(ActionEvent event) {

    String i1 = txt1.getText();

    int tx1 = Integer.parseInt(i1);

    t1.setText(Integer.toString(tx1));
       

    String i2 = txt2.getText();
    int tx2 = Integer.parseInt(i2);
    t2.setText(Integer.toString(tx2));

    String i3 = txt3.getText();
    int tx3 = Integer.parseInt(i3);
    t3.setText(Integer.toString(tx3));

    String i4 = txt4.getText();
    int tx4 = Integer.parseInt(i4);
    t4.setText(Integer.toString(tx4));

    String i5 = txt5.getText();
    int tx5 = Integer.parseInt(i5);
    t5.setText(Integer.toString(tx5));
}

This code throws the following exception:

Caused by: java.lang.NumberFormatException: For input string: ""
    at java.base/java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
    at java.base/java.lang.Integer.parseInt(Integer.java:662)
    at java.base/java.lang.Integer.parseInt(Integer.java:770)
    at fx2/sample.Controller.calculer(Controller.java:98)
    ... 62 more

Answer 1

You can check if the field is empty and if so, assign 0 to the variable, for example (because you mentioned that you want to create a bill).

For this, change your code snippets like in this example with i2:

String i2 = txt2.getText();
int tx2 = Integer.parseInt(i2);
t2.setText(Integer.toString(tx2));

to

String i2 = txt2.getText();
int tx2 = 0;
if(i2.length() > 0) {
     tx2 = Integer.parseInt(i2);
}
t2.setText(Integer.toString(tx2));

You can do this with all code snippets you have (for i1 to i5).