我正在使用 Vue.js 3.0 和 TypeScript 进行开发。
\n我想定义一个在多个组件中使用的枚举。
\n我应该如何以及在文件中写入什么?
目录
\nsrc/\n\xe2\x94\x9c components/\n\xe2\x94\x82 \xe2\x94\x9c ParentComponent.vue\n\xe2\x94\x82 \xe2\x94\x94 ChildComponent.vue\n\xe2\x94\x94 App.vue\nRun Code Online (Sandbox Code Playgroud)\n子组件.vue
\n<template>\n <p>{{ color }}</p>\n</template>\n\n<script lang="ts">\nimport { defineComponent, PropType } from 'vue'\n\nenum Color {\n red = 1,\n blue\n}\n\nexport default defineComponent({\n props: {\n color: { type: Color, required: true }\n }\n})\n</script>\nRun Code Online (Sandbox Code Playgroud)\n父组件.vue
\n<template>\n <div>\n <ChildComponent\n :color="state.color"\n />\n </div>\n</template>\n\n<script lang="ts">\nimport ChildComponent from './ChildComponent.vue'\nimport { defineComponent, reactive } from 'vue'\n\n// duplicate\nenum Color {\n red = 1,\n blue\n}\n\ninterface State {\n color: Color\n}\n\nexport …Run Code Online (Sandbox Code Playgroud) 通常,在定义时-tableView:commitEditingStyle:forRowAtIndexPath,可以通过滑动将所有单元格切换到编辑模式.
但是,我想-tableView:commitEditingStyle:forRowAtIndexPath只为特定的细胞启用.
那可能吗?
我想从NSUserDefaults更改对象get.
但是在执行以下代码时,应用程序崩溃并显示错误消息:
*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '-[__NSCFDictionary setObject:forKey:]: mutating method sent to immutable object’
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我有这个代码.
NSUserDefaults* pref = [NSUserDefaults standardUserDefaults];
NSMutableArray* data = [[NSMutableArray alloc]init];
data = [[pref objectForKey:@"Data"] mutableCopy];
for (NSArray* array in data) { //make object mutable
[array mutableCopy];
for (NSDictionary* dic in array) {
[dic mutableCopy];
}
}
[data[0][1] setObject:@"YES" forKey:@"isChecked"]; //for example
[pref setObject: data forKey: @"Data"];
[pref synchronize];
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数据结构:
NSMutableArray* arr1 = [@[[@{@"name":@"abc", @"isChecked":@"YES"} mutableCopy], [@{@"name":@"def", @"isChecked":@"NO"} mutableCopy]] mutableCopy];
NSMutableArray* …Run Code Online (Sandbox Code Playgroud) objective-c nsuserdefaults nsmutablearray nsmutabledictionary ios
我正在随机生成0到11之间的数字,如下所示:
int n = arc4random() % 12;
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但是,我想不要输出5或6.我怎样才能做到这一点?