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NSUserDefault存在-iPHONE SDK_Iphone_Cocoa_Xcode_Nsuserdefaults - Fatal编程技术网

NSUserDefault存在-iPHONE SDK

NSUserDefault存在-iPHONE SDK,iphone,cocoa,xcode,nsuserdefaults,Iphone,Cocoa,Xcode,Nsuserdefaults,如果NSUserDefault对象是否保存在“if”语句中,我将如何签入该语句?我真的不知道怎么称呼它。。所以这是一个很短的问题 谢谢戴夫的答案是正确的,但我会跳过明确的零测试: if ([[NSUserDefaults standardUserDefaults] objectForKey:@"Foo"]) { NSLog(@"An object is saved under \"Foo\"!"); } Dave的答案是正确的,但我会跳过明确的零测试: if ([[NSUserDefa

如果NSUserDefault对象是否保存在“if”语句中,我将如何签入该语句?我真的不知道怎么称呼它。。所以这是一个很短的问题


谢谢

戴夫的答案是正确的,但我会跳过明确的零测试:

if ([[NSUserDefaults standardUserDefaults] objectForKey:@"Foo"]) {
    NSLog(@"An object is saved under \"Foo\"!");
}

Dave的答案是正确的,但我会跳过明确的零测试:

if ([[NSUserDefaults standardUserDefaults] objectForKey:@"Foo"]) {
    NSLog(@"An object is saved under \"Foo\"!");
}

这是一种风格选择。我喜欢在比较中直截了当地说:)@Dave DeLong:当然。我的也是一种风格选择,只是指出了另一种选择。一致性更重要。:)这是一种风格选择。我喜欢在比较中直截了当地说:)@Dave DeLong:当然。我的也是一种风格选择,只是指出了另一种选择。一致性更重要。:)