How to comment code in react native: 1. Within the HTML tag node, use "{/* */}" to comment; 2. Outside the HTML tag node, use "/**/" to comment, a single line can be commented with "//".
The operating environment of this tutorial: windows7 system, react native0.6&&react16 version, this method is applicable Suitable for all brands of computers.
Recommended related tutorials: React video tutorial
React Native comments are too particular, errors are reported frequently, and they are not smart. Here is a summary of the comments .
Problem presentation
The code is as follows:
//标题栏 ① <view> ②<view><text>Header</text> </view> //Tab栏 <scrollabletabview> <defaulttabbar></defaulttabbar>}//默认样式,Tab栏不可滑动 tabBarUnderlineStyle={styles.lineStyle}//下划线 tabBarActiveTextColor='#FF0000'> <myflatlist> <touchablenativefeedback> <text>{item.key}</text> </touchablenativefeedback> } /></myflatlist></scrollabletabview></view>
It runs normally before adding comments. After adding comments, various reports are reported. Error.
It’s very strange. After investigation, we found:
>. Please note that when using // as a comment, the comment content must not be in any html tag, otherwise it will be regarded as the text content to be displayed.
For example, although the //Tab bar above is outside ②, it is still inside ①. It will be regarded as the text to be displayed, and an error will be reported. At this time, the comment should be {/* General comment , surrounded by {}" for multiple lines */}
#react native uses JSX language, combining JS and html. All comments are as follows:
var content = ( <nav> {/* 一般注释, 用 {} 包围 */} <person></person> </nav> );
Add comments in JSX Easily they are just JS expressions. You just need to surround the part to be commented with {} within the child nodes of a tag (not the outermost).
class ReactDemo extends Component { render() { return ( <View style={styles.container}> {/*标签子节点的注释*/} <Text style={styles.welcome} //textAlign='right' textShadowColor='yellow' /*color='red' textShadowRadius='1'*/ > React Native! </Text> </View> ); } }
Comment outside the tag node and The usual comments are the same, use "/**/", use "//" for a single line.
Note:
When using // as a comment, please note that the comment content must not be in any html tag, otherwise it will be regarded as The text content to be displayed
comments are generally {/**/} for multiple lines. If it is not within any tag, you can use //, } followed by comments //
More programming related knowledge, Please visit: Introduction to Programming! !
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