File Read/Write Script Example
Below is a trivial example of how to use the FILE class to perform file reading and writing using the CANCapture scripting block. This example also shows how to use strings and access individual characters of the string based on index.
It would also be very easy to use this class to perform logging of CAN messages to a file using your own custom format.
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| void OnStartCapture(ScriptBlock block) | |
| { | |
| //This is the file I/O class that encapsulates all file access | |
| file f; | |
| //Open file | |
| f.open("c:\\test.csv", "rb"); | |
| string str = ""; | |
| //Loop through reading the file until the end | |
| int fsize = f.getSize(); | |
| while (f.getPos() < fsize) | |
| { | |
| //Test all reading of variables as well as the get/set/movepos functions | |
| str += f.readInt8() + "\n"; | |
| f.movePos(-1); | |
| str += f.readInt8() + "\n"; | |
| f.setPos(f.getPos() - 1); | |
| str += f.readInt8() + "\n"; | |
| str += f.readInt16() + "\n"; | |
| str += f.readInt32() + "\n"; | |
| str += f.readInt64() + "\n"; | |
| str += f.readUInt8() + "\n"; | |
| str += f.readUInt16() + "\n"; | |
| str += f.readUInt32() + "\n"; | |
| str += f.readUInt64() + "\n"; | |
| str += f.readFloat() + "\n"; | |
| str += f.readDouble() + "\n"; | |
| //Test reading of string | |
| string s; | |
| f.readString(s, 3); | |
| str += s + "\n"; | |
| //Test reading of large string and treating it as a | |
| //BYTE buffer | |
| int size = f.readString(s, 1000); | |
| str += "Length " + s.length() + "\n"; | |
| str += s += "\n"; | |
| int x; | |
| for (x = 0; x < size; ++x) | |
| { | |
| uint8 b = s[x]; | |
| str += b + " "; | |
| } | |
| str += "\n"; | |
| } | |
| block.ClearOutputText(); | |
| block.PrintOutputText(str, true, false, false, false); | |
| f.close(); | |
| } | |
| void OnStopCapture(ScriptBlock block) | |
| { | |
| //This is the file I/O class that encapsulates all file access | |
| file f; | |
| //Open file | |
| f.open("c:\\test.csv", "wb"); | |
| int i = 0; | |
| for (i = 0; i < 5; ++i) | |
| { | |
| //Test writing of all variable types | |
| f.writeInt8(i); | |
| f.writeInt16(i); | |
| f.writeInt32(i); | |
| f.writeInt64(i); | |
| f.writeUInt8(i); | |
| f.writeUInt16(i); | |
| f.writeUInt32(i); | |
| f.writeUInt64(i); | |
| f.writeFloat(i); | |
| f.writeDouble(i); | |
| //Test wtriting of constant string | |
| f.writeString("abc", 3); | |
| //Test writing of string, but using as if it were a byte | |
| //buffer and accessed by index | |
| string s; | |
| int x; | |
| for (x = 0; x < 1000; ++x) | |
| { | |
| s += "0"; | |
| s[x] = x % 32 + 48; | |
| } | |
| f.writeString(s, 1000); | |
| } | |
| //Close the file - destructor would also safely do this too | |
| f.close(); | |
| block.ClearOutputText(); //Clear this scripts output window | |
| block.PrintOutputText("Capture stopped\n", false, false, false, false); //Print to the output window | |
| } | |
