Fix(InputItem): add try catch to getSelection (#3236)

[zack24q]

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This change is 

[codecov]

Codecov Report

Merging #3237 into master will increase coverage by 0.02%.
The diff coverage is 83.33%.

@@            Coverage Diff            @@
##           master   #3237      +/-   ##
=========================================
+ Coverage   60.07%   60.1%   +0.02%     
=========================================
  Files          92      92              
  Lines        2282    2286       +4     
  Branches      656     656              
=========================================
+ Hits         1371    1374       +3     
- Misses        902     903       +1     
  Partials        9       9

Flag	Coverage Δ
#web	60.1% <83.33%> (+0.02%)	⬆️

Impacted Files	Coverage Δ
components/input-item/index.tsx	64.19% <83.33%> (+0.27%)	⬆️
components/locale-provider/locale-provider.tsx	100% <0%> (ø)	⬆️

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[likezero]

备注下为啥会异常？

[likezero]

05b9d86

[likezero]

感觉这样写会比较直观。

try {
  
      prePos = el.selectionEnd;
} catch (e) {
   prePos = 0;
}

[zack24q]

这样子改TS会报错：不能将类型“number | null”分配给类型“number”

[zack24q]

异常的原因注释已加哈

[ziluo]

catch到错误只是console.warn么，没有兜底措施吗？

[zack24q]

兜底就是不处理光标位置了

[doxiaodong]

这个问题改了好几次了的样子。。