Tag Archives: javascript

Uni-app Error when assigning a value to a component: [system] TypeError: Cannot read property ‘name‘ of undefined

[system] TypeError: Cannot read property ‘name’ of undefined

This error occurs because some of the attributes in your curly brackets are undefined
1. Wrong attribute name
2. Another case: when the data is obtained asynchronously, there is no such data attribute during initialization
in my case, case 2, the value of the string is relatively deep, and the definition is only one level up
value structure:

{
    "id": 105,
    ...
    "dealer": {
        "sn": null,
        "password": null,
        "name": "xx",
        "departmentSn": null,
    },
    ...
},

		<view class="content-row">
			 <text class="cause">待处理：</text>
			 <text class="cause-detail" v-if="claim_detail_basic_list" >{{claim_detail_basic_list.dealer.name}}</text>
			</view>

This side has done error prevention processing

v-if="claim_detail_basic_list"

Because the value object has to be further “claim”_ detail_ basic_ List. Dealer. Name ”

chunk-vendors.js:3874 [Vue warn]: Error in render: "TypeError: Cannot read property 'name' of undefined"

The solution can go one step further.

<view class="content-row">
			 <text class="cause">ToDoList:</text>
			 <text class="cause-detail" v-if="claim_detail_basic_list.dealer" >{{claim_detail_basic_list.dealer.name}}</text>
			</view>

{{claim_ detail_ basic_ List. Dealer. Name}
OK! Reason: the deep object was not created and there was no attribute of the object when it was initialized.

[Solved] This.getoptions is not a function when installing sass loader and less loader

After installing sass loader and less loader, we report module build failed: typeerror: this.getoptions is not a function with lang = “less” or lang = “sess”

less：

npm install [email protected] --save-dev

Version reduced to 5.0.0

sess：

npm uninstall sass-loader // unisntall current version
 
npm install [email protected] --save-dev

Reinstall version 7.3.1

[Solved] Turf.js error: uncaught (in promise) error: the solution of invalid unit

Solution for turf.js error: Uncaught (in promise) Error: Invalid unit
Error code (npm i turf):

import turf from 'turf';

var line = turf.lineString([[-83, 30], [-84, 36], [-78, 41]]);
var options = {units: 'miles'};

var along = turf.along(line, 200, options); // Wrong

Correct code (NPMI @ turf/turf)

import * as turf from '@turf/turf';

var line = turf.lineString([[-83, 30], [-84, 36], [-78, 41]]);
var options = {units: 'miles'};

var along = turf.along(line, 200, options);

Unknown custom element: ＜component＞ – did you register the component correctly

This error occurs when creating dynamic components using JSX:

Unknown custom element: <component> - did you register the component correctly

The reason is that we take it for granted that in template syntax, dynamic components are created like this:

<component :is='dev-chart'></component>

The JSX syntax should be:

<component is={'dev-chart'}></component>

Then the above error appears, hhhhh.

Therefore, the correct way to write it is to use createElement instead of component is, which is the price of going deep into the bottom layer.

Source: https://blog.csdn.net/kw269937519/article/details/114080530

Using pop-up window and I18N, error in render: “typeerror: cannot read property” appears_ T ‘of undefined’ solution

First, make sure to hang Vue under window.vm in main.js (the name of VM can be customized)

window.vm = new Vue({
  el: '#app',
  i18n,
  router,
  store,
  render: h => h(App)
})

Secondly, when writing multi language in the pop-up box, you need to add VM.
for example, when writing multi language, you need to write {$t ('xxxxx ')} or this. $t ('xxx')
then you need to write {VM. $t ('xxxxx ')} or this. VM. $t ('xxxxx') or this

Method to solve uncaught typeerror: cannot set property ‘onclick’ of null error

Problem analysis: this error occurs when the JS file is placed in the head tag and the onclick event is bound

reason:

W3school introduces that the browser loads the button node before executing JS. When the browser parses from top to bottom, the button node bound to onclick cannot be found

For example:

<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Events</title> 
<script>
    var Btn = document.getElementById('btn');
    Btn.onclick = function(){    
        console.log("push the button ");        
    }
</script> 
</head> 
<body> 
   <button id="btn">Calculation</button> 
</body>
</html>

This error will appear, as shown in the following figure:

Solution 1: use the JS content in window ο nl ο Ad = function () {} wrap it up

<!DOCTYPE HTML>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <title>Events</title>
    <script>
        window.onload = function () {
            var Btn = document.getElementById('btn');
            Btn.onclick = function () {
                console.log("push the button ");
            }
        }
    </script>
</head>
<body>
    <button id="btn">Calculation</button>
</body>
</html>

Solution 2: load the JS file at the bottom

<!DOCTYPE HTML>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <title>Events</title>
</head>
<body>
    <button id="btn">Calculation</button>
    <script>
        var Btn = document.getElementById('btn');
        Btn.onclick = function () {
            console.log("push the button ");
        }
    </script>
</body>
</html>

The page console error [Vue warn]: Invalid prop: custom validator check failed for prop “status“

Invalid prop: custom validator check failed for prop “status” encountered during project debugging##

First of all, I was confused. I went to the prop and didn’t have status. I really couldn’t figure out what was going on. Through the global search of status, I realized that it was the problem of style components. Because of the company’s confidentiality, I really wanted to simulate the code

<el-progress  :percentage="stepPercentage(item.step)"  status="error"></el-progress>

The status in this code is the key to error reporting. The reason is that I added an unknown attribute error of status, which makes it unrecognizable

be careful

1. The value of status can only be one of “success/exception/warning”. Other values will give the above warning. If you have to judge according to the conditions and need to give the default color, you can assign null [null, no quotation marks] to the value

<el-progress  :percentage="stepPercentage(item.step)" :status="item.step == 4 ?'success' :null"></el-progress>

2. You can’t have spaces in the parameters following status. You need to correct the format

@requestbody: How to Use or Not Use

First of all, note that @ requestbody accepts the JSON string
so write this

dataType:"json",
contentType: 'application/json',
data: JSON.stringify(data.field),

Instead of @ requestbody, you can directly receive the JSON type

dataType:"json",
data: data.field,

The situation of not using @ requestbody
front end page

$.ajax({
		url: "http://localhost:8081/role//saveOrUpdate",
		method:"post",
	   dataType:"json",     
			// contentType: 'application/json',
		data: data.field,   
		success(data){
			console.log("======================")
				console.log(data.field)
			if(data.code == 200){
			layer.msg('add success', function () {
			 window.location = 'list.html';
				}); 
				}
		},
error(data){
	console.log(data)
	if(data.code != 200){
layer.msg(data); 
								}
								}
							});

Back end:

@PostMapping("/saveOrUpdate")
    public Result saveOrUpdate(Roles roles){
        System.out.println(roles);
        boolean saveOrUpdate = roleService.saveOrUpdate(roles);
        if(saveOrUpdate == true)
            return Result.succ(null);
        else
            return Result.fail("failed to add");
    }

Using @ requestbody
front end:

$.ajax({
								url: "http://localhost:8081/role//saveOrUpdate",
								method:"post",
								dataType:"json",
								contentType: 'application/json',   
								data: JSON.stringify(data.field),  
								success(data){
									console.log("======================")
									console.log(data.field)
									if(data.code == 200){
										layer.msg('add success', function () {
										    window.location = 'list.html';
										}); 
									}
								},
								error(data){
									console.log(data)
									if(data.code != 200){
										layer.msg(data); 
								}
								}
							});

back-end

@PostMapping("/saveOrUpdate")
    public Result saveOrUpdate(@RequestBody Roles roles){
        System.out.println(roles);
        boolean saveOrUpdate = roleService.saveOrUpdate(roles);
        if(saveOrUpdate == true)
            return Result.succ(null);
        else
            return Result.fail("failed to add");
    }

It is invalid to submit the content directly after pasting it on the mobile terminal of Vue HTML5 editor

Modify the source code vue-html5-editor.js
Directory:

open this file, search for contenteditable, add id = “container”

and then search for Keyup
comment code

 // content.addEventListener('keyup', function () {
 //     this$1.$emit('change', content.innerHTML);
 //     this$1.saveCurrentRange();
 // }, false);

Add code

const handleListenChange = (mutationsList, observer) => {
 this$1.$emit('change', content.innerHTML);
 this$1.saveCurrentRange();
}
const mutationObserver = new MutationObserver(handleListenChange)
const element = document.querySelector('#container')
const options = {
 attributes: true,
 childList: true,
 subtree: true,
 characterData: true
}

It’s like this on the whole

I’ve looked at others and modified it myself. This question is more detailed than that of the blogger. Link to attach. If you have any other questions, take a look
CSDN of Dashen