Question

我的iOS项目中有url变量，当我在DEBUG模式下构建项目时，我希望它指向http://localhost:3000/api，但是当我为RELEASE构建项目时，我希望url变量指向http://example.com/api

所以我已经草拟了以下内容，

#ifdef DEBUG
    // want to use this variable on DEBUG build
    NSURL *url = [NSURL URLWithString:@"http://localhost:3000/api/"];
#endif
    // want to use this variable on RELEASE build
    NSURL *url = [NSURL URLWithString:@"http://example.com/api/"];

但是Xcode抱怨说我已经宣布了url变量。

Answer 1

您应该在设定值之前定义变量试试这段代码：

NSURL *url = [NSURL URLWithString:@"http://localhost:3000/api/"];
NSURL *url = [NSURL URLWithString:@"http://example.com/api/"];

Answer 2

为什么不这样做：

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.4.5/angular.min.js"></script>

<table ng-app="myApp" ng-controller="myController as ctrl">
    <tr ng-repeat="(key, range) in ctrl.vars">
        <td ng-switch="ctrl.getTypeOf(range)">
            <div ng-switch-when="string">It's a string</div>
            <div ng-switch-when="object">It's an object</div>
            <div ng-switch-when="number">It's a number</div>
            <div ng-switch-when="array">It's an array</div>
            <div ng-switch-when="null">It's null</div>
            <div ng-switch-when="undefined">It's undefined</div>
            <div ng-switch-default>It's something else</div>
        </td>
    </tr>
</table>

Answer 3

试

'use strict'

import { task, parallel, series, src, dest, watch, plugins } from './gulp';

import { startStagingServer } from './servers';

import { solution } from './solution.map';

const path = require('path');

task('serve', parallel(startStagingServer, watchStyles);

function watchStyles() {
  watch([ solution.src.styles ], series(formatStyles, compileStyles))
}

function formatStyles(done) {
  return src([ solution.src.styles ])
    .pipe(plugins.csscomb())
    .pipe(dest(solution.src.mount)) // the root of the solution
}

function compileStyles() {
  return src([ solution.src.styles ])
    .pipe(plugins.sass().on('error', plug.sass.logError))
    .pipe(dest(path.join(solution.dest.stage, 'serve')));
}

Answer 4

嗯，你做了宣布它。想一想：这是条件代码。那么，如果定义#ifdef DEBUG // want to use this variable on DEBUG build NSURL *url = [NSURL URLWithString:@"http://localhost:3000/api/"]; #else // want to use this variable on RELEASE build NSURL *url = [NSURL URLWithString:@"http://example.com/api/"]; #endif，代码实际上会是什么样子？它看起来像这样：

DEBUG

嗯，这是非法的。

如何使用两个具有相同名称的变量

4 个答案: