用于textarea的ngModel在angular 2中不起作用 [英] ngModel for textarea not working in angular 2

问题描述

我正在尝试使用ngModel在textarea中打印json对象.

I am trying to print json object in textarea using ngModel.

我已经完成以下操作:

<textarea style="background-color:black;color:white;" [(ngModel)]='rapidPage' rows="30" cols="120">                             
</textarea>

我想在textarea中加载json对象.上面的代码将rapidPage对象加载到textarea中，但将textarea值显示为[object Object].

I want to load the json object in textarea. The above code is loading the rapidPage object in textarea but its showing textarea value as [object Object].

对象:

 this.rapidPage = {            
        "pageRows": [
            {
                "sections": [
                    {
                        "sectionRows": [
                            {
                                "secRowColumns": [                                       
                                ]
                            },
                            {
                                "secRowColumns": [
                                    {
                                        "colName": "users"
                                    }
                                ]
                            },
                            {
                                "secRowColumns": [
                                    {
                                        "colName": "sample"
                                    }
                                ]
                            }
                        ],
                        "width": 0
                    }
                ]
            }
        ],
        "pageName": "DefaultPage",
        "pageLayout": "DEFAULT_LAYOUT",
        "editMode": true
    };

我想将数据加载为字符串. 有输入吗?

I want to load the data as string. any inputs?

推荐答案

假设您想按原样绑定rapidPage，并且只会在textArea中写入有效的JSON.

Assuming that you want to bind rapidPage as it is and will only write valid JSON in the textArea.

• 更改值时需要PARSE，在文本区域中显示时需要STRINGIFY.

• You need to PARSE it when changing the value, and STRINGIFY when showing in textarea.

> StackBlitz DEMO

在组件代码中执行以下操作

Do the following in your Component code

  rapidPage = {"pageRows":[{"sections":[{"sectionRows":[{"secRowColumns":[]},{"secRowColumns":[{"colName":"users"}]},{"secRowColumns":[{"colName":"sample"}]}],"width":0}]}],"pageName":"DefaultPage","pageLayout":"DEFAULT_LAYOUT","editMode":true}; 
  // your object

  get rapidPageValue () {
    return JSON.stringify(this.rapidPage, null, 2);
  }

  set rapidPageValue (v) {
    try{
    this.rapidPage = JSON.parse(v);}
    catch(e) {
      console.log('error occored while you were typing the JSON');
    };
  }

模板用法:

<textarea [(ngModel)]='rapidPageValue' rows="30" cols="120">                             
</textarea>

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