小编Md.*_*ain的帖子

如果我的数组没有某些值或某些值在 html 中未定义，我想这样做，只是不要尝试从数组中获取它。

空数组：[{0：未定义}]

全阵列：

[
{0: "Name"},  
{1: "img.src"},  
{2: name: string,  family: string, age: number} 
]

0: "Name" , 1: "img.src" 2 {name: string, family: string; 年龄：数}

我的尝试不起作用：

   <div *ngFor="let fam of familyArray" class="grid-item">
        <button ion-button>
          <img *ngIf="fam[1] != undefined && fam[1] != null "  class="selectImg" src="{{fam[1]}}" alt="">
        </button>
        <span *ngIf="fam[2].name != undefined && family[2].age != undefined  && family[2].age != null && family[2].name != null " class="image-text">{{fam[2].name}}, {{family[2].age}}m.</span>
        <p *ngIf="fam[2].family != undefined  && fam[2].family != null "  class="family-status">{{fam[2].family}}</p> …

我是OOP的初学者,最近开始用C#编写代码.(在Visual Studio 2017控制台应用程序中工作.)在搜索教程后,我会在这里试试运气.

我正在尝试制作一个简单的程序,允许用户通过询问输入来制作新的对象书(或多个).我知道如何手动创建类的对象,但不知道如何对用户输入执行相同的操作.这是我到目前为止的代码:

public class book
{
    //variables
    private string title;
    private string author;
    private string genre;
    private string series;

    //constructor
    public book(string _titel, string _author, string _genre, string _series)
    {
        this.titel = _titel;
        this.author = _author;
        this.genre = _genre;
        this.series = _series;
    }

    //method to ask user for input to create book
    public void createBook()
    {

    }

有人可以帮帮我吗？我被错误困住了几天我试图使用包选项排除它但似乎不起作用。

caused by: com.android.builder.merge.DuplicateRelativeFileException: More than one file was found with OS independent path 'com/google/i18n/phonenumbers/data/PhoneNumberMetadataProto_WF'
at com.android.builder.merge.StreamMergeAlgorithms.lambda$acceptOnlyOne$2(StreamMergeAlgorithms.java:75)
at com.android.builder.merge.StreamMergeAlgorithms.lambda$select$3(StreamMergeAlgorithms.java:100)
at com.android.builder.merge.IncrementalFileMergerOutputs$1.create(IncrementalFileMergerOutputs.java:86)
at com.android.builder.merge.DelegateIncrementalFileMergerOutput.create(DelegateIncrementalFileMergerOutput.java:61)
at com.android.build.gradle.internal.transforms.MergeJavaResourcesTransform$1.create(MergeJavaResourcesTransform.java:386)
at com.android.builder.merge.IncrementalFileMerger.updateChangedFile(IncrementalFileMerger.java:221)
at com.android.builder.merge.IncrementalFileMerger.mergeChangedInputs(IncrementalFileMerger.java:190)
at com.android.builder.merge.IncrementalFileMerger.merge(IncrementalFileMerger.java:77)
at com.android.build.gradle.internal.transforms.MergeJavaResourcesTransform.transform(MergeJavaResourcesTransform.java:419)
at com.android.build.gradle.internal.pipeline.TransformTask$2.call(TransformTask.java:239)
at com.android.build.gradle.internal.pipeline.TransformTask$2.call(TransformTask.java:235)
at com.android.builder.profile.ThreadRecorder.record(ThreadRecorder.java:102)
at com.android.build.gradle.internal.pipeline.TransformTask.transform(TransformTask.java:230)
at sun.reflect.GeneratedMethodAccessor312.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
at org.gradle.api.internal.project.taskfactory.IncrementalTaskAction.doExecute(IncrementalTaskAction.java:50)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:39)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:26)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$1.run(ExecuteActionsTaskExecuter.java:131)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:300)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:292)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:174)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90)
at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:120)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:99)
... 115 more

这里是这个项目中使用的 gradle 依赖项。

dependencies { …

我想用来从文件中Openxml抽象。我不知道该怎么做，并且在官方示例中没有找到任何有关它的示例。请帮我。"OLE package"".docx"

这是我的尝试：

\n

1. 我通过“MS Office 2016”构建了一个名为 的 Docx 文件"Test.docx"，并将".zip"文件插入到"Test.docx". 我打开"Open XML SDK 2.5 Productivity Tool"Watch "Test.docx"，找到了这个（图 1），但我没有获得任何有关如何通过反射代码提取此 zip 文件的信息。

   \n
\n

2. 然后我尝试使用 C# 并SharpCompress.dll提取该".zip"文件，接下来是代码：

   \n

    class Program\n {\n     static void Main(string[] args)\n     {\n         string filepath = @"C:\\Users\\\xe5\xae\x87\xe5\xae\x99\xe6\x97\xa0\xe6\x95\x8c\xe5\xb8\x85\xe5\xb0\x8f\xe4\xbc\x99\\Desktop\\test.docx";\n\n         OleFileTest(filepath);\n     }\n\n     public static void OleFileTest(string filepath)\n     {\n         try\n         {\n             using (WordprocessingDocument Docx = WordprocessingDocument.Open(filepath, true))\n             {\n                 Body body = Docx.MainDocumentPart.Document.Body;\n\n …

   Run Code Online (Sandbox Code Playgroud)

考虑这个代码片段：

SELECT 
    vbs.SKUID, SKUName, SUM(vbs.Quantity) AS Qty
FROM   
    BatchStocks AS vbs
WHERE  
    vbs.SKUID IN (Here i have almost 12000 SKU)
    AND vbs.StoreID IN (%q)
    AND vbs.StockType = %n
GROUP BY
    vbs.SKUID, vbs.SKUName

在这种where情况下，我有将近 12000 个 SKUID，这需要很多时间来执行语句。你能建议我如何改进这个查询吗？

我想在我的 android 项目中添加第三方 sdk。谁能告诉我一步一步的过程......我试过但不能......我的过程：

1. 将 jar 文件复制并粘贴到 libs 文件夹中
2. 在 build.gradle 文件中添加依赖
3. 然后清理项目并构建