我的状态是{visibilityFilter: "completed"}或{visibilityFilter: "todo"}。基于此,我想为一个元素分配类名。像这样
<span {this.state.visibilityFilter=="completed"?className="active":className:""}>Completed</span>
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但这不起作用。我尝试了各种变化
{<span this.state.visibilityFilter=="completed"?className="active":className:"">Completed</span>}
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但是他们都没有工作。我知道,如果我在return语句外创建变量并将其分配为HTML,则它可以工作。像这样,
let classCompleted = this.state.visibilityFilter == "completed"? "active":"";
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然后,
<span className={`$(classCompleted)`}></span>
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但是我想知道如何在return语句中评估类。