我正在学习
Swift并且一直在试图弄清楚我无法加载文件.事实证明,代码在Xcode中工作,但在操场上不起作用.这是什么原因？
这是代码：
func testFileLoad(){
let myFilePath: String = "/Users/clay/Desktop/test.txt"
let t: Bool = NSFileManager.defaultManager().fileExistsAtPath(myFilePath)
print(t)
let s: String = try! String(contentsOfFile: myFilePath,encoding: NSUTF8StringEncoding)
print(s)
do {
let p: String = try String(contentsOfFile: myFilePath,encoding: NSUTF8StringEncoding)
print(p)
} catch {
print("nope")
}
}
在Xcode的测试模块中运行,它可以正常工作并打印我希望的控制台.
Test Suite 'Selected tests' started at 2015-08-05 14:24:15.977
Test Suite 'swiftgraphTests' started at 2015-08-05 14:24:15.978
Test Case '-[swiftgraphTests.swiftgraphTests testFileLoad]' started.
true
this is a test
this is a test
Test Case '-[swiftgraphTests.swiftgraphTests testFileLoad]' passed (0.001 seconds).
Test Suite 'swiftgraphTests' passed at 2015-08-05 14:24:15.979.
Executed 1 test,with 0 failures (0 unexpected) in 0.001 (0.001) seconds
Test Suite 'Selected tests' passed at 2015-08-05 14:24:15.979.
Executed 1 test,with 0 failures (0 unexpected) in 0.001 (0.002) seconds
在操场上,我明白了：
我在这做错了什么？我不正确地使用操场吗？
如果你去菜单
“View” -> “Debug Area” -> “Show Debug Area”
您将看到完整错误：“您无权从Playground *访问文件系统.”
解决方法是使用Project Navigator将文件包含在Playground中.
转到菜单
“View” -> “Navigators” -> “Show Project Navigator”
然后将文件拖放到“Resources”文件夹中.
然后使用NSBundle获取路径.
func testFileLoad() {
// get the file path for the file from the Playground's Resources folder
guard let path = NSBundle.mainBundle().pathForResource("test",ofType: "txt") else {
print("Oops,the file is not in the Playground")
return
}
// keeping the examples from your question
let s: String = try! String(contentsOfFile: path,encoding: NSUTF8StringEncoding)
print(s)
do {
let p: String = try String(contentsOfFile: path,encoding: NSUTF8StringEncoding)
print(p)
} catch {
print("nope")
}
}
testFileLoad()
*实际上,您只能访问包含Playground共享数据的/ var /文件夹,而Playground只提供快捷方式. Playground导航器中的此文件夹实际上代表/ var /文件夹,并且对于每个Playground都是唯一的.您可以使用NSBundle查看其地址：
NSBundle.mainBundle().resourcePath