FileStorage fs("test.yml", FileStorage::WRITE);    fs << "MyString" << "123abc";    fs.release();// Read data    FileStorage fs2("test.yml", FileStorage::READ);    string str = fs2["MyString"];    cout << "MyString = " << str << endl;    fs2.release();

In OpenCV, the FileStorage class can read and write data in the file. If you write the string "123abc" into the file, it will shows with quotation mark in the file. Now I want to read this string from the file into a string variable, you need to keep the quotation mark in the file which should be see as follows:

MyString: "123abc"

Now it can be read without problem, but if you change it to the followings:

MyString: 123abc

This will not gonna work this time, but if the string is not start with a number, it will work. I might treat it as a bug in the OpenCV. The three different situation is as follows:

MyString: "123abc"    // WorkMyString: 123abc      // NOT workMyString: abc123      // Work

In sum, when you want to read a string into a variable, if it starts with a number, you need to add the quotation marker to the whole string in the file.

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