That happens when svn encounters a conflict: You changed a file, the file on the server was changed and it cannot (easily) be merged automatically. You need to decide what is the correct solution now.
Subversion just adds the diff into your source file (and creates files next to it, called OriginalName.mine (unchanged) and OriginalName.rsomething (unchanged, server version)).
Fix the conflict and tell subversion that this is resolved.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…