反应如何用另一个数组设置状态数组?
React how to setState array with another array?
我想用另一个数组的值设置一个数组。我应该为此使用推送吗?
嗯,在这种情况下,我正在尝试获取 selectedOptions 数组并使用 selectedOptions 值设置 selectedTags 数组
但只需从 selectedOptions 数组中压入 1 个值!
所以,有人可以提示一下如何映射数组并从中获取值吗?
handleChange = (selectedOptions) => {
this.setState({ selectedOptions });
let options = [];
selectedOptions.map((v) => options.push(v.value));
this.setState((state) => ({
selectedTags: options
}));
}
数组映射
您可以使用Array.map
函数:
const data = [
{id: 1, value: '1'},
{id: 2, value: '2'},
{id: 3, value: '3'},
{id: 4, value: '4'},
{id: 5, value: '5'},
{id: 6, value: '6'},
{id: 7, value: '7'},
]
const onlyValues = data.map(d => d.value)
console.log(onlyValues)
通过传播添加到数组
const data = [1,2,3,4,5,6,7,8,9,10]
const toBeAdded = 11
const newData = [...data, toBeAdded]
console.log(newData)
const toBeAddedArray = [11,12,13,14,15,16]
const newDataArray = [...data, ...toBeAddedArray]
console.log(newDataArray)
我想用另一个数组的值设置一个数组。我应该为此使用推送吗?
嗯,在这种情况下,我正在尝试获取 selectedOptions 数组并使用 selectedOptions 值设置 selectedTags 数组
但只需从 selectedOptions 数组中压入 1 个值!
所以,有人可以提示一下如何映射数组并从中获取值吗?
handleChange = (selectedOptions) => {
this.setState({ selectedOptions });
let options = [];
selectedOptions.map((v) => options.push(v.value));
this.setState((state) => ({
selectedTags: options
}));
}
数组映射
您可以使用Array.map
函数:
const data = [
{id: 1, value: '1'},
{id: 2, value: '2'},
{id: 3, value: '3'},
{id: 4, value: '4'},
{id: 5, value: '5'},
{id: 6, value: '6'},
{id: 7, value: '7'},
]
const onlyValues = data.map(d => d.value)
console.log(onlyValues)
通过传播添加到数组
const data = [1,2,3,4,5,6,7,8,9,10]
const toBeAdded = 11
const newData = [...data, toBeAdded]
console.log(newData)
const toBeAddedArray = [11,12,13,14,15,16]
const newDataArray = [...data, ...toBeAddedArray]
console.log(newDataArray)