The following text files into Xcode Plist problems (can not be read into a string and the program crashes)

Currently I have a task, is to make a text file into a property list plist, two problems are encountered:
1 put into supporting files in a text file (also copy) after just under Xcode click on the txt file (about 200KB), Xcode will crash crash. To view this document only with an external text editor. What is the reason of this problem is? How to solve? I suspect that the file is too big and has a relationship because another small txt file no problem.
(2) The first step I want to read the entire file into a string, I use the following method:
NSString * filePath = [[NSBundle mainBundle] pathForResource: @ "Contact" ofType: @ "txt"];
NSString * bookString = [NSString stringWithContentsOfFile: filePath encoding: NSUTF8StringEncoding error: nil];
However, the program did not find the debug text file read into the string. May I ask how to solve this problem?
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Document processing problems chant
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Program access space, only pieces of the file under Document file is writable!
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Thank you for help, the problem has been resolved
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The second problem is how to solve? Hey, just encountered this problem. . The landlord does not talk about solving results. . .