Question

我生成一个包含一系列嵌套对象的对象数组（在元素＆＃39; failReasons＆＃39;和＆＃39;照片＆＃39;） - 然后我想将结果数组发布为JSON到Web API，它会期望一个对象列表，带有嵌套的对象列表。第一部分工作 - 数组接收对象列表并可以解析它们，但是，当将我的数组转换为JSON时，嵌套数组将保留为空。

这是我生成的数组：以下是我对其进行字符串化时的样子：

{"capeNo":"ABCD1234","insDate":"2016-11-10 15:03:18","inspector":"User.Name","inspectionResult":"Pass","comments":"","site":"Site Name","dismCompleteDate":"","failReasons":[],"photos":[]}

正如您所看到的，failReasons在字符串化之前在其数组中有6个对象，现在只是一个空数组。

我使用以下代码生成数组：

接口：

export interface inspectionUpload {
        capeNo: string;
        insDate: string;
        inspector: string;
        inspectionResult: string;
        comments: string;
        site: string;
        dismCompleteDate;
        failReasons: Array<Object>;
        photos: Array<Object>;
}

export interface inspectionFailures {
        failCategory: string;
        failReason: string;
        resolution: string;
        inspectionId: string;
}

export interface inspectionPhotos {
        base64: string;
}

这会填充数组：

this.sql.query('SELECT rowid,* FROM InspectionResults_tbl').then((res) => {
    var arr = []

    for (var i = 0; i < res.res.rows.length; i++) {
        var item = res.res.rows.item(i);
        var header: inspectionUpload = {
            capeNo: item.capeNo,
            insDate: item.inspectionDT,
            inspector: item.inspectedBy,
            inspectionResult: item.result,
            comments: item.comment,
            site: this.SharedService.site,
            dismCompleteDate: item.dismantleDate,
            failReasons: < inspectionFailures[] > [],
            photos: < inspectionPhotos[] > []
        }

        if (item.result == 'Fail') {
            console.log(item);
            this.sql.query('SELECT * FROM InspectionFailures_tbl WHERE inspectionId = ?', [item.rowid]).then((res) => {
                for (var i = 0; i < res.res.rows.length; i++) {
                    var item = res.res.rows.item(i);
                    header.failReasons.push({
                        failCategory: item.failCategory,
                        failReason: item.failreason,
                        resolution: item.resolution,
                        FRId: item.FRId
                    })
                }
            })
        }

        this.sql.query('SELECT * FROM InspectionPhotos_tbl WHERE inspectionId = ?', [item.rowid]).then((res) => {
            for (var i = 0; i < res.res.rows.length; i++) {
                var item = res.res.rows.item(i);
                header.photos.push({
                    base64: item.base64
                })
            }
        })



        arr.push(header);
        if ((i + 1) == res.res.rows.length) upload(arr)
    }
})

最后，将其字符串化：

function upload(a) {
          console.log(a);
          console.log(JSON.stringify(a));
        }

非常感谢帮助：）

Answer 1

这可能是因为您在解析promise之前打印了字符串化数组。

        this.sql.query('SELECT * FROM InspectionFailures_tbl WHERE inspectionId = ?', [item.rowid]).then((res) => {
            for (var i = 0; i < res.res.rows.length; i++) {
                var item = res.res.rows.item(i);
                header.failReasons.push({
                    failCategory: item.failCategory,
                    failReason: item.failreason,
                    resolution: item.resolution,
                    FRId: item.FRId
                })
            }
        })
    ...

    arr.push(header);
    if ((i + 1) == res.res.rows.length) upload(arr)

如果你执行下面的代码，它会正确地字符串化（这不是正确的方法，我只是证明你不能进行字符串化，直到当时的推送完成填充数组... ）：

        var queryComplete = false;

        this.sql.query('SELECT * FROM InspectionFailures_tbl WHERE inspectionId = ?', [item.rowid]).then((res) => {
            for (var i = 0; i < res.res.rows.length; i++) {
                var item = res.res.rows.item(i);
                header.failReasons.push({
                    failCategory: item.failCategory,
                    failReason: item.failreason,
                    resolution: item.resolution,
                    FRId: item.FRId
                })
            }
            queryComplete = true;
        })
    ...

    while ( !queryComplete ){
        //noop
    }

    arr.push(header);
    if ((i + 1) == res.res.rows.length) upload(arr)

带有嵌套对象数组TypeScript / JS的JSON.Stringify数组

1 个答案: