EN您的问题是，您还没有告诉TypeScript“我应该在这里做什么”，所以执行一直持续到函数的末尾，在那里...
在那里您不会返回任何东西。因此，错误消息是“函数缺少结束返回语句，返回类型不包括'undefined'”。
demo: typescript playground demo 主要代码: interface Example { children?: Example[] } const example: Example = { children: [{ children: [] }] } if (example.children) { for (let i = 0; i < example.children.length; i++) { if (example.children[i] && example.children[i].children)...
obj.test是string，因此test也是string，不可能是undefined。
问Typescript -缩短包含重复if表达式的代码ENTypeScript中提供了箭头表达式，通过箭头表达式可以简化我们的...
Issue description Preload not working if id is of type int8 Expected Behavior Preload should work when id is of type int8 Actual Behavior Preload is returning undefined when providing an id of type int8. Steps to reproduce Example entity...
class Super { prop: any = undefined; } class Derived extends Super { prop() {} } new Derived().prop(); // runtime error: undefined is not a function You can still use a function to initialize prop in Derived: class Super { prop: any = undefined; } class Derived extends Super {...
Thefind()method returns the first occurrence of the target element if it successfully executes, or else it returnsundefined. varfruitsArray:string[]=['apple','orange','lichi','banana'];if(fruitsArray.find(e=>e==='orange')){console.log('orange is present in array');} ...
和typescript部分: 1234567 produceFassungsLink(titel: string, iri: string) { if(titel !== undefined && iri !== undefined) { return titel.split('/')[0] + '---' + iri.split('raeber/')[1]; } else { return 'Linkinformation has not arrived yet'; } } 感谢和最好的作为, 简 相关...
TypeScript Kopírovat function normalTemplateBody(): NormalTemplateBodyContext | undefined Returns NormalTemplateBodyContext | undefined Inherited Method DetailsaddAnyChild<T>(T) Add a parse tree node to this as a child. Works for internal and leaf nodes. Does not set parent link; other add ...