在Javascript中将对象承诺转换为字符串

JavaScript React.js

JinJin

2020-03-23

我正在使用React,Next.Js,semantic-ui-react和Solidity。我的目标是打印出用户地址(从MetaMask)和ProjectTitle(由用户设置)作为语义UI反应卡的元信息。可以打印出“页眉”中的地址,但是我无法将ProjectTitle打印为“元”。标题应该是一个字符串,但是我收到一个对象承诺。

static async getInitialProps() {
    const projects = await factory.methods.getDeployedProjects().call();
    return {
        projects
    };
}

async getProjectTitle(address) {
    let title;
    try {
        title = await factory.methods.projectTitle(address).call();
    } catch (err) {
        console.log('err');
    }
    return title;
}

renderProjects() {
    const items = this.props.projects.map(address => {
        return {
            header: address,
            color: 'green',
            description: (
                <Link route={`/projects/${address}`}>
                    <a>View Project</a>
                </Link>
            ),
            **meta: this.getProjectTitle(address)**,
            fluid: true,
            style: { overflowWrap: 'break-word' }
        };
    }, );
    return <Card.Group items={items} />
}

团结合同的一部分:

address[] public deployedProjects;
mapping(address => string) public projectTitle;

function createProject(string startup, string title, string deadline, string description, uint wage) public {
    address newProject = new Project(startup, title, deadline, description, wage, msg.sender);
    projectTitle[newProject] = title;
    deployedProjects.push(newProject);
}

function getDeployedProjects() public view returns (address[]) {
    return (
        deployedProjects
    );
}

基本框架来自Stephen Grider的Udemy课程“以太坊和团结:完整的开发人员指南”。

第2948篇《在Javascript中将对象承诺转换为字符串》来自Winter(https://github.com/aiyld/aiyld.github.io)的站点

1个回答
卡卡西Near 2020.03.23

没有直接的方法将对象承诺转换为字符串。继续处理的唯一方法是调用一个await函数或使用.then()一个回调函数。

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