我认为这对CSS网格来说是一个很好的例子.在您的模板中，我根本不用担心rowSpans，只需将所有数据放入其自己的列中即可(发票和期望值具有单独的列).

为 tr 标记添加规则到 display:grid ，并根据需要定义 grid-template-columns .然后，您可以将 grid-area 应用于每列，并使用 grid-template-areas 规则定义"rowSpan".

如果希望标题显示不同，还可以为 tr.mat-h​​eader-row 定义一组不同的 grid-template-areas 规则./p>

我已经编写了一个小示例，该示例应具有与您所寻找的解决方案类似的解决方案: https://stackblitz.com/edit/angular-u2b8qa?file = src/app/table-basic-example.scss

I'm struggling with the following. I want to change my basic html table to a mat-table. But I can not find a way to merge the two rows on the first two columns.

I've got the mat-table on top and the basic html table on the bottom:

[![enter image description here][1]][1]

What I want in my mat table is the following: for each reference + invoice I want two rows, one with invoiced and one with expected, just like in my bottom table.

My basic html table is as following:

<table>
  <thead>
    <th *ngFor= "let column of headersContainers">
      {{column}}
    </th>
  </thead>

  <tbody *ngFor = "let container of completeContainers">
    <th rowspan = "2" >{{container.containerReference}}</th>
    <th rowspan = "2" >{{container.invoiceReference}}</th>
      <td>Invoiced</td>
      <td>{{container.InvoicedCosts.OFC | currency :'€ '}}</td>
      <td>{{container.InvoicedCosts.THC | currency :'€ '}}</td>
      <td>{{container.InvoicedCosts.BAF | currency :'€ '}}</td>
      <td>{{container.InvoicedCosts.Total | currency :'€ '}}</td>
    <tr> 
      <td>Expected</td> 
      <td>{{container.ExpectedCosts.OFC | currency :'€ '}}</td>
      <td>{{container.ExpectedCosts.THC | currency :'€ '}}</td>
      <td>{{container.ExpectedCosts.BAF | currency :'€ '}}</td>
      <td>{{container.ExpectedCosts.Total | currency :'€ '}}</td>
    </tr>
  </tbody>
</table>

While my mat-table html is as following:

<table mat-table [dataSource]="dataSource">

  <ng-container matColumnDef="containerReference">
    <th mat-header-cell *matHeaderCellDef [rowSpan]="2"> Reference </th>
    <td mat-cell *matCellDef="let container"> {{container.containerReference}} </td>
  </ng-container>

  <ng-container matColumnDef="InvoiceReference">
    <th mat-header-cell *matHeaderCellDef [rowSpan]="2"> Invoice </th>
    <td mat-cell *matCellDef="let container"> {{container.invoiceReference}} </td>
  </ng-container>

  <ng-container matColumnDef="InvoicedOrExpected">
    <th mat-header-cell *matHeaderCellDef> Invoiced or expected </th>
    <td mat-cell *matCellDef="let container"> Invoiced </td>
  </ng-container>

  <ng-container matColumnDef="OHC">
    <th mat-header-cell *matHeaderCellDef> Ocean handling costs </th>
    <td mat-cell *matCellDef="let container"> {{container.OHC}} </td>
  </ng-container>

  <ng-container matColumnDef="THC">
    <th mat-header-cell *matHeaderCellDef> Terminal handling costs </th>
    <td mat-cell *matCellDef="let container"> {{container.THC}} </td>
  </ng-container>

  <ng-container matColumnDef="BAF">
    <th mat-header-cell *matHeaderCellDef> Bunker adjustment factor </th>
    <td mat-cell *matCellDef="let container"> {{container.BAF}} </td>
  </ng-container>

  <ng-container matColumnDef="Total">
    <th mat-header-cell *matHeaderCellDef> Total </th>
    <td mat-cell *matCellDef="let container"> {{container.Total}} </td>
  </ng-container>

  <tr mat-header-row *matHeaderRowDef="headersContainers"></tr>
  <tr mat-row *matRowDef="let row; columns: headersContainers;"> </tr>

</table>

My dataSource looks as follows:

[
    {
        "containerReference": "20DV HLXU1234567",
        "invoiceReference": "109554 (20000678)",
        "InvoicedCosts": {
            "OFC": 1023.0,
            "THC": 100.0,
            "BAF": 67.0,
            "Total": 1190.0
        },
        "ExpectedCosts": {
            "OFC": 465.0,
            "THC": 205.0,
            "BAF": 285.0,
            "Total": 955.0
        }
    },
    {
        "containerReference": "20DV HLXU2234567",
        "invoiceReference": "109554 (20000678)",
        "InvoicedCosts": {
            "OFC": 3445.0,
            "THC": 65.0,
            "BAF": 77.0,
            "Total": 3587.0
        },
        "ExpectedCosts": {
            "OFC": 465.0,
            "THC": 205.0,
            "BAF": 285.0,
            "Total": 955.0
        }
    }
]

Quick note that I can change the dataSource setup since I'm using ArrayNode in java.

EDIT:

I've changed the the HTML file to this:

<h1>Costs per container</h1>
<mat-checkbox (change)="switchEvent($event)" labelPosition ="before">Show correctly invoiced containers</mat-checkbox>

<table mat-table [dataSource]="dataSource">

  <!--Container reference-->
  <ng-container matColumnDef="containerReference">
    <th mat-header-cell *matHeaderCellDef> Reference </th>
    <td mat-cell *matCellDef="let container"> {{container.containerReference}} </td>
  </ng-container>

  <!--Invoice reference-->
  <ng-container matColumnDef="invoiceReference">
    <th mat-header-cell *matHeaderCellDef> Invoice </th>
    <td mat-cell *matCellDef="let container"> {{container.invoiceReference}} </td>
  </ng-container>

  <!--Invoiced columns-->
  <ng-container matColumnDef="invoicedOHC">
    <th mat-header-cell *matHeaderCellDef> Ocean handling costs </th>
    <td mat-cell *matCellDef="let container"> {{container.InvoicedCosts.OFC}} </td>
  </ng-container>

  <ng-container matColumnDef="invoicedTHC">
    <th mat-header-cell *matHeaderCellDef> Terminal handling costs </th>
    <td mat-cell *matCellDef="let container"> {{container.InvoicedCosts.THC}} </td>
  </ng-container>

  <ng-container matColumnDef="invoicedBAF">
    <th mat-header-cell *matHeaderCellDef> Bunker adjustment factor </th>
    <td mat-cell *matCellDef="let container"> {{container.InvoicedCosts.BAF}} </td>
  </ng-container>

  <ng-container matColumnDef="invoicedTotal">
    <th mat-header-cell *matHeaderCellDef> Total </th>
    <td mat-cell *matCellDef="let container"> {{container.InvoicedCosts.Total}} </td>
  </ng-container>

  <!--expected columns-->
  <ng-container matColumnDef="expectedOHC">
    <th mat-header-cell *matHeaderCellDef></th>
    <td mat-cell *matCellDef="let container"> {{container.ExpectedCosts.OFC}} </td>
  </ng-container>

  <ng-container matColumnDef="expectedTHC">
    <th mat-header-cell *matHeaderCellDef></th>
    <td mat-cell *matCellDef="let container"> {{container.ExpectedCosts.THC}} </td>
  </ng-container>

  <ng-container matColumnDef="expectedBAF">
    <th mat-header-cell *matHeaderCellDef></th>
    <td mat-cell *matCellDef="let container"> {{container.ExpectedCosts.BAF}} </td>
  </ng-container>

  <ng-container matColumnDef="expectedTotal">
    <th mat-header-cell *matHeaderCellDef></th>
    <td mat-cell *matCellDef="let container"> {{container.ExpectedCosts.Total}} </td>
  </ng-container>

  <!--Invoiced or expected columns-->
  <ng-container matColumnDef="invoicedLabel">
    <th mat-header-cell *matHeaderCellDef> Invoiced or expected </th>
    <td mat-cell *matCellDef="let container"> Invoiced </td>
  </ng-container>

  <ng-container matColumnDef="expectedLabel">
    <th mat-header-cell *matHeaderCellDef></th>
    <td mat-cell *matCellDef="let container"> Expected </td>
  </ng-container>

  <tr mat-header-row *matHeaderRowDef="headersContainers"></tr>
  <tr mat-row *matRowDef="let row; columns: headersContainers;"> </tr>

</table>

And the SCSS is as following:

table {
  width: 100%;
}

.mat-column-containerReference {grid-area: containerReference;}
.mat-column-invoiceReference {grid-area: invoiceReference;}
.mat-column-invoicedOHC {grid-area: invoicedOHC;}
.mat-column-invoicedTHC {grid-area: invoicedTHC;}
.mat-column-invoicedBAF {grid-area: invoicedBAF;}
.mat-column-invoicedTotal {grid-area: invoicedTotal;}
.mat-column-expectedOHC {grid-area: expectedOHC;}
.mat-column-expectedTHC {grid-area: expectedTHC;}
.mat-column-expectedBAF {grid-area: expectedBAF;}
.mat-column-expectedTotal {grid-area: expectedTotal;}
.mat-column-expected {grid-area: expected;}
.mat-column-invoiced {grid-area: invoiced;}
.mat-column-invoicedLabel {grid-area: invoicedLabel;}
.mat-column-expectedLabel {grid-area: expectedLabel;}

tr {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-template-areas: 
            "containerReference invoiceReference invoicedLabel invoicedOHC invoicedTHC invoicedBAF invoicedTotal"
            "containerReference invoiceReference expectedLabel expectedOHC expectedTHC expectedBAF expectedTotal";
}

tr.mat-header-row {
  grid-template-areas: 
        "containerReference invoiceReference invoicedLabel invoicedOHC invoicedTHC invoicedBAF invoicedTotal";
  
  .mat-column-expected,
  .mat-column-expectedLabel {
    display: none;
  }
}

td, th {
  display: flex;
  align-items: center;
  padding-left: 5px !important;
  border-right: 1px solid rgba(128, 128, 128, .4);
}

This results in the merged rows how I wanted, but the columns do not allign with the rows:

[![enter image description here][2]][2]

EDIT 2:

after the comment of RobbieAreBest, I've changed the scss part grid-template-columns: repeat(4, 1fr); to grid-template-columns: repeat(7, 1fr);

This gave me the following result: [![enter image description here][3]][3]

Either, it still does not look perfect. If anyone knows how to make the cell allign, that would be nice! [1]: https://i.stack.imgur.com/JzP51.png [2]: https://i.stack.imgur.com/fnut4.png [3]: https://i.stack.imgur.com/Vx7cK.png

I think this would be a good case for CSS grid. In your template, I wouldn't worry about rowSpans at all, just get all your data into its own column (have separate columns for Invoiced and Expected values).

Add a rule for your tr tags to display:grid and define you grid-template-columns as needed. You could then apply a grid-area to each column and define your 'rowSpan' by using a grid-template-areas rule.

You could also define a different set of grid-template-areas rules for tr.mat-header-row if you would like the header to display differently.

I've worked up a little example that should have a solution similar to what you are looking for: https://stackblitz.com/edit/angular-u2b8qa?file=src/app/table-basic-example.scss