Question

我想使用Typescript为Knockout-Validation库（https://github.com/Knockout-Contrib/Knockout-Validation）编写自定义规则。我有一个.ts文件，我正在尝试输出这段代码：

export function enableCustomValidators() {
    ko.validation.rules["myRule"] = {
        validator: function (val: string, otherVal: string) {
            return val === otherVal;
    },
    message: 'The field must equal {0}',
}

    ko.validation.registerExtenders();
}

在构建时我收到此错误：错误TS7017元素隐式具有“任意”类型，因为类型'KnockoutValidationRuleDefinitions'没有索引签名。

使用Typescript添加新的自定义验证器的正确方法是什么？

由于

Answer 1

Most likely an issue with the type definitions which does not have an indexer to add custom validations. You can augment the KnockoutValidationRuleDefinitions interface temporarily in your code:

declare global {
    interface KnockoutValidationRuleDefinitions {
        [customValidationRuleName: string]: KnockoutValidationRuleDefinition
    }
}

Or explicitly cast ko.validation.rules as any to silence the compiler:

(ko.validation.rules as any)["myRule"] = {
    validator: function (val: string, otherVal: string) {
        return val === otherVal;
    },
    message: 'The field must equal {0}',
}

If you want this fixed in the type definitions itself you can raise a PR against the DefinitelyTyped reporitory with the indexer added to the KnockoutValidationRuleDefinitions interface.

Typescript Knockout验证自定义规则

1 个答案: