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javascriptes6-promise

two .then in axios

I am trying to load the Ag-grid. I saw this code sample, but I don’t know why they use two times .then. Can anyone help me to understand it? Thank you

beforeMount() {
    this.columnDefs = [
        {headerName: 'Make', field: 'make'},
        {headerName: 'Model', field: 'model'},
        {headerName: 'Price', field: 'price'}
    ];

    fetch('https://api.myjson.com/bins/15psn9')
        .then(result => result.json())
        .then(rowData => this.rowData = rowData);
}
Solution

  • Because your response.json() call itself returns another Promise, as you can read up in the documentation about Body.json(). The reason for that is that response body contains a stream that needs to get parsed and converted into JS data structures before you can use it.