摘要：根據(jù)頁(yè)面中中的例子匯總修改而成。代碼代碼流逝時(shí)間計(jì)時(shí)器按鈕點(diǎn)擊計(jì)數(shù)流逝時(shí)間計(jì)時(shí)器寫(xiě)法實(shí)時(shí)求解一元二次方程調(diào)用組件制作動(dòng)畫(huà)效果代碼僅在例中使用

根據(jù)http://reactjs.cn/react/docs/...頁(yè)面中Starter Kit 15.3.1中的例子匯總修改而成。

HTML代碼

JS代碼

const container1 = document.getElementById("container1")
const container2 = document.getElementById("container2")
const container3 = document.getElementById("container3")
const container4 = document.getElementById("container4")
const container5 = document.getElementById("container5")
const container6 = document.getElementById("container6")


//1 "Hello" + name
function Welcome(props) {
    return 
 Hello, { props.name } < /h1>;
}

const element = < Welcome name = "Diary" / > ;
ReactDOM.render(
    element,
    container1
);

//2 流逝時(shí)間計(jì)時(shí)器
var Elapsed = React.createClass({
    render: function () {
        var elapsed = Math.round(this.props.elapsed / 100);
        var seconds = elapsed / 10 + (elapsed % 10 ? "" : ".0");
        var message =
            "React has been successfully running for " + seconds + " seconds.";

        return 
 { message } < /p>;
    }
});

var start = new Date().getTime();
setInterval(function () {
    ReactDOM.render( < Elapsed elapsed = { new Date().getTime() - start }
        / > ,
        container2
    );
}, 50);

//3 按鈕點(diǎn)擊計(jì)數(shù)

var Counter = React.createClass({
    getInitialState: function () {
        return { 
            count: 2,
            sum: 100
        };
    },
    handleClick: function () {
        this.setState({
            count: this.state.count * this.state.count,
        });
    },
    handleDoubleClick: function () {
        this.setState({
            count: 2,
            sum: 1000
        })
    },
    render: function () {
        return ( 
            < button onClick = { this.handleClick } onDoubleClick = { this.handleDoubleClick }>
            sum - count: { this.state.sum - this.state.count } < /button>
        );
    }
});
ReactDOM.render( < Counter / > ,
    container3
);


//4 流逝時(shí)間計(jì)時(shí)器（ES6寫(xiě)法）

class ExampleApplication extends React.Component {
    render() {
        var elapsed = Math.round(this.props.elapsed / 100);
        var seconds = elapsed / 10 + (elapsed % 10 ? "" : ".0");
        var message =
            `React has been successfully running for ${seconds} seconds.`;

        return 
 { message } < /p>;
    }
}
var start = new Date().getTime();
setInterval(() => {
    ReactDOM.render( < ExampleApplication elapsed = { new Date().getTime() - start }/>,
        container4
    );
}, 50);


//5 實(shí)時(shí)求解一元二次方程

var QuadraticCalculator = React.createClass({
  getInitialState: function() {
    return {
      a: 1,
      b: 3,
      c: -4
    };
  },

  /**
   * This function will be re-bound in render multiple times. Each .bind() will
   * create a new function that calls this with the appropriate key as well as
   * the event. The key is the key in the state object that the value should be
   * mapped from.
   */
  handleInputChange: function(key, event) {
    var partialState = {};
    partialState[key] = parseFloat(event.target.value);
    this.setState(partialState);
  },

  render: function() {
    var a = this.state.a;
    var b = this.state.b;
    var c = this.state.c;
    var root = Math.sqrt(Math.pow(b, 2) - 4 * a * c);
    var denominator = 2 * a;
    var x1 = (-b + root) / denominator;
    var x2 = (-b - root) / denominator;
    return (
      

        
          ax2 + bx + c = 0
        
        
Solve for x:
        

          
            a: 
          
          

          
            b: 
          
          

          
            c: 
          
          

          x: {x1}, {x2}
        
      
    );
  }
});

ReactDOM.render(
  ,
  container5
);


//6 調(diào)用React組件CSSTransitionGroup制作動(dòng)畫(huà)效果

var CSSTransitionGroup = React.addons.CSSTransitionGroup;
var INTERVAL = 2000;

var AnimateDemo = React.createClass({
getInitialState: function() {
  return {current: 0};
},

componentDidMount: function() {
  this.interval = setInterval(this.tick, INTERVAL);
},

componentWillUnmount: function() {
  clearInterval(this.interval);
},

tick: function() {
  this.setState({current: this.state.current + 1});
},

render: function() {
  var children = [];
  var colors = ["#fac", "#cdc", "#36d", "#ca0", "#0aa"];
  for (var i = this.state.current, pos=0; i < this.state.current + colors.length; i++, pos++) {
    var style = {
      left: pos * 128,
      background: colors[i % colors.length]
    };
    children.push(
{i}
);
  }
  return (
    
      {children}
    
  );
}
});

ReactDOM.render(
,
container6
);

CSS代碼（僅在例6中使用）

.example-enter,
.example-leave {
  -webkit-transition: all .25s;
  transition: all .25s;
}

.example-enter,
.example-leave.example-leave-active {
  opacity: 0.01;
}

.example-leave.example-leave-active {
  margin-left: -128px;
}

.example-enter {
  margin-left: 128px;
}

.example-enter.example-enter-active,
.example-leave {
  margin-left: 0;
  opacity: 1;
}

.animateExample {
  display: block;
  height: 128px;
  position: relative;
  width: 384px;
}

.animateItem {
  color: white;
  font-size: 36px;
  font-weight: bold;
  height: 128px;
  line-height: 128px;
  position: absolute;
  text-align: center;
  -webkit-transition: all .25s; /* TODO: make this a move animation */
  transition: all .25s; /* TODO: make this a move animation */
  width: 128px;
}