<< Graphics`PlotField`

<< Graphics`PlotField3D`

PlotVectorField[{x, 0}, {x, -2, 2}, {y, -2, 2}]

PlotVectorField[{x - y, x + y}, {x, -2, 2}, {y, -2, 
        2}]

PlotVectorField[{x^2 - y - 1, x - y}, {x, -2, 2}, {y, -2, 
        2}]

PlotVectorField3D[{x - y, x + y, z}, {x, -2, 2}, {y, -2, 
        2}, {z, -2, 2}]