84669 person learning
152542 person learning
20005 person learning
5487 person learning
7821 person learning
359900 person learning
3350 person learning
180660 person learning
48569 person learning
18603 person learning
40936 person learning
1549 person learning
1183 person learning
32909 person learning
You have two-way binding and you have not input anything. Then your printSingle.szLat is undefined.
If you need an empty string for "", you can initialize it
data () { return { printSingle: { szLat: '' } } }
The variable is defined, but when there is no value, the value is undefined
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
You have two-way binding and you have not input anything. Then your printSingle.szLat is undefined.
If you need an empty string for "", you can initialize it
The variable is defined, but when there is no value, the value is undefined