我正在尝试将以下代码发送到 React js 中的子组件:
\n\n{\n carPhoto: "../../images/small-logo.jpg",\n make: "Mercedes",\n price: "\xe2\x82\xac20000",\n desc: "Vivamus gravida magna massa in cursus mi"\n}\nRun Code Online (Sandbox Code Playgroud)\n\n现在我试图将desc分成两行。\n我尝试使用\\n、\\r、\\r\\n
\n\ndesc: "Vivamus gravida magna<br /> massa in cursus mi"\ndesc: "Vivamus gravida magna\\nmassa in cursus mi"\ndesc: "Vivamus gravida magna\\r\\nmassa in cursus mi"\nRun Code Online (Sandbox Code Playgroud)\n\n但没有任何效果。有什么建议吗?
\n我在react js中有以下代码:
'use strict';
module.exports = {
homePage: {
sliderTitle: 'Creative portfolio',
loginTitle: 'Do you already <b>have</b> an account?'
},
registrationPage: {
foo: 'bar'
}
};
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当我尝试使用那些标签时
var EN = require('./en');
{EN.homePage.loginTitle}
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但{EN.homePage.loginTitle}返回带有b标签的字符串.
如何将这个b标签应用于单词?
为什么这不起作用:
class Slider extends React.Component {
constructor(props){
super(props);
this.state = {
top : 0,
responsiveImg : ""
};
}
componentWillMount(){
const bodyWidth = window.innerWidth;
const responsiveSliderImg = "responsiveSliderImg";
if((bodyWidth >= 415) && (bodyWidth < 473)){
this.setState({responsiveImg: responsiveSliderImg});
console.log("The state is : " + this.state.responsiveImg);
}
}
}
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我正在尝试将类名添加到componentWillMount函数中的状态,但它不起作用.在控制台日志中我得到的状态是:,因此状态为空.
任何的想法?
我有下一个html结构:
<div class="offerButtons">
<button type="reset" class="btnReset"><span> No </span></button>
<input type="text" class="offerInput" />
<button type="submit" class="btnSubmit"><span> Yes </span></button>
</div>
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而我的CSS如下:
.offerButtons {
display: table;
width: 100%;
background-color: yellow;
}
.btnReset, .btnSubmit {
border: 1px solid red;
border-radius: 50%;
width: 30px;
height: 30px;
display: table-cell;
text-align: center;
vertical-align: middle;
}
.btnReset span, .btnSubmit span{
color: red;
}
.offerInput {
height: 31px;
margin: 0 5px;
display: table-cell;
}
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btnReset和btnSubmit具有固定的宽度。我想要的是那两个按钮的宽度固定,而inout字段占据其余宽度。
我想得到类似的东西:
但是现在,有了这段代码,我得到了:
任何的想法?
这是jsfiddle
我有一个Django模型,如下所示:
class BodyHeight(models.Model):
seats = models.ForeignKey(to=Seats)
name = models.CharField(max_length=127, null=True, blank=True)
key = models.CharField(max_length=100, null=True)
data = models.TextField(null=True, blank=True)
class Meta:
verbose_name_plural = "Body heights"
def __str__(self):
return self.name
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然后在data字段中存储json数据,如下所示:
{"url": "https://some_url=/BE?category=COMMERCIAL, "images": ["url_to_some_image"]}
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我想仅在Django管理面板中显示该字段的网址。
我现在有:
class BodyHeightAdmin(admin.ModelAdmin):
search_fields = ('name', )
list_display = ('id', 'name', 'key', )
list_display_links = ('id', 'name', 'key', )
admin.site.register(BodyHeight, BodyHeightAdmin)
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那是没有数据字段。如果我data在list_display其中添加的字段显示的是整个json(丑陋的格式),但我只想要url。
任何想法如何做到这一点?
我试图在鼠标移动时在画布上画一个圆圈,但没有成功。我的代码如下:
var damages_canvas = document.getElementById('damages-area');
var ctx_damages = damages_canvas.getContext('2d');
var circle_rect = damages_canvas.getBoundingClientRect();
var circle_drag = false;
var circle_canvas_update = true;
var circles = [];
var markerColor = "#f00";
damages_canvas.addEventListener('mousedown', drawCircleMouseDown, false);
damages_canvas.addEventListener('mouseup', drawCircleMouseUp, false);
damages_canvas.addEventListener('mousemove', drawCircleMouseMove, false);
requestAnimationFrame(updateCircleCanvas);
function updateCircleCanvas(){
if(circle_canvas_update){
drawCircleCanvas();
circle_canvas_update = false;
}
requestAnimationFrame(updateCircleCanvas);
}
function drawCircle(circle){
var startX = circle.startX,
endX = circle.endX,
startY = circle.startY,
endY = circle.endY;
ctx_damages.clearRect(0,0,damages_canvas.width,damages_canvas.height);
ctx_damages.beginPath();
ctx_damages.moveTo(startX, startY + (endY-startY)/2);
ctx_damages.bezierCurveTo(startX, startY, endX, startY, endX, startY + (endX-startY)/2);
ctx_damages.bezierCurveTo(endX, endY, …Run Code Online (Sandbox Code Playgroud)在我的settings.py我有以下代码:
LANGUAGE_CODE = \'en\' \nUSE_I18N = True \nUSE_L10N = True\nUSE_DECIMAL_SEPARATOR = True\nDECIMAL_SEPARATOR = ","\nUSE_THOUSAND_SEPARATOR = True\nTHOUSAND_SEPARATOR = "."\nRun Code Online (Sandbox Code Playgroud)\n\n在我的模板中,我使用的数字如下:
\n\n{% load humanize %}\n{% load i18n %}\n{% load l10n %}\n<div>{% trans "Price" %}: \xe2\x82\xac <b>{{ payment|floatformat:2|intcomma }}</b></div>\nRun Code Online (Sandbox Code Playgroud)\n\n但数字仍然是18,300.00我希望它是18.300,00。
\n\n任何想法?
\n我在前端使用 React 和 Graphql,在后端使用 Django 和 Graphene。
我希望能够下载报告的 pdf 文件。我尝试使用突变来做到这一点,如下所示:
const [createPdf, {loading: createPdfLoading, error: createPdfError}] = useMutation(CREATE_PDF)
const handleCreatePDF = async (reportId) => {
const res = await createPdf({variables: {reportId: parseInt(reportId) }})
debugger;
};
export const CREATE_PDF = gql`
mutation ($reportId: Int!) {
createPdf (reportId: $reportId){
reportId
}
}
`;
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在后端,我有这样的事情:
class CreatePDFFromReport(graphene.Mutation):
report_id = graphene.Int()
class Arguments:
report_id = graphene.Int(required=True)
def mutate(self, info, report_id):
user = info.context.user
if user.is_anonymous:
raise GraphQLError("You are not logged in!")
report …Run Code Online (Sandbox Code Playgroud) 如何使用 React js 创建简单的微调器?
假设我有这样的代码:
let cars = [
{id: 1, name: "Golf"},
{id: 2, name: "Audi"},
{id: 3, name: "Passat"},
{id: 4, name: "Bmw"}
];
class Test extends React.Component {
constructor(props){
super(props);
this.state = {
loading: true
}
}
componentDidMount(){
this.setState({loading: false})
}
render(){
let content = this.state.loading ? <div>Loading</div> : cars.map((c, i) => <div key={i}>{c.name}</div>)
return (
<div>{content}</div>
)
}
}
React.render(<Test />, document.getElementById('container'));
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我试图loading在汽车列表未加载时进行显示。
这是小提琴
任何想法?
我已经在React中注册了,我需要将文件上传到服务器。这些文件需要Base64编码。
对其进行编码的函数如下:
getBase64(file) {
let document = "";
let reader = new FileReader();
reader.readAsDataURL(file);
reader.onload = function () {
document = reader.result;
};
reader.onerror = function (error) {
console.log('Error: ', error);
};
return document;
}
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而处理表单的下一步按钮的功能如下:
handleNextButtonClick(event){
event.preventDefault();
let data = {domainId: this.props.user[0].domainId, name: steps.stepThree, values: this.state.files};
let idCard = this.state.files.filter(file => file.file_type === "ID_CARD")[0].values.file;
let statuses = this.state.files.filter(file => file.file_type === "STATUTES")[0].values.file;
let blankLetterHead = this.state.files.filter(file => file.file_type === "LETTER_HEAD")[0].values.file;
let companyPhoto = this.state.files.filter(file => file.file_type === "COMPANY_PICTURE")[0].values.file;
let …Run Code Online (Sandbox Code Playgroud)