Question

我是TypeScript的初学者（很明显，我来自Java Universe）。我目前正试图做一个这样的映射器：

public getApercuTypePrestationFromTypePrestationEX044(typePrestationEX044: TypePrestationEX044): ApercuTypePrestation {
        let apercuTypePrestation: ApercuTypePrestation;
        if (null != typePrestationEX044) {
            apercuTypePrestation = new ApercuTypePrestation();
            apercuTypePrestation.codeTypePrestation == typePrestationEX044.code;
            apercuTypePrestation.libelleTypePrestation == typePrestationEX044.libelle;
        }

        console.log("A = " + typePrestationEX044.code);
        console.log("B = " + apercuTypePrestation.libelleTypePrestation);

        return apercuTypePrestation;
    }

但是它显然不起作用：在控制台中，我有： A = A8C B =未定义

我该如何解决？

Answer 1

您使用的是==而不是=。我将==更改为=，现在应该可以使用了。

public getApercuTypePrestationFromTypePrestationEX044(typePrestationEX044: TypePrestationEX044): ApercuTypePrestation {
        let apercuTypePrestation: ApercuTypePrestation;
        if (null != typePrestationEX044) {
            apercuTypePrestation = new ApercuTypePrestation();
            apercuTypePrestation.codeTypePrestation = typePrestationEX044.code;
            apercuTypePrestation.libelleTypePrestation = typePrestationEX044.libelle;
        }

        console.log("A = " + typePrestationEX044.code);
        console.log("B = " + apercuTypePrestation.libelleTypePrestation);

        return apercuTypePrestation;
    }

在打字稿中， ==或===用于比较而不是分配，以便分配必须使用=

的值

更新

我还注意到您正在错误地检查typePrestationEX044中是否为null。

更改此：

if (null != typePrestationEX044) {
            apercuTypePrestation = new ApercuTypePrestation();
            apercuTypePrestation.codeTypePrestation = typePrestationEX044.code;
            apercuTypePrestation.libelleTypePrestation = typePrestationEX044.libelle;
        }

为此

if (typePrestationEX044) {
            apercuTypePrestation = new ApercuTypePrestation();
            apercuTypePrestation.codeTypePrestation = typePrestationEX044.code;
            apercuTypePrestation.libelleTypePrestation = typePrestationEX044.libelle;
        }

此if条件将自动检查undefined，null或boolean

在块外访问变量

1 个答案: