分享一个栅格计算的操作字符串，我写的

     对两个栅格图层多叠加，在第一个图层没值或者值为0时，取第二个图层的值，当两个图层都有值且都不为0时，采用权重计算法，进行计算，同时对计算结果取整。

strTmp = "con(IsNull([" + R1 + "]), con(IsNull([" + R2 + "]), 0, [" + R2 + "]), "
                        +"con(IsNull([" + R2 + "]), [" + R1 + "], con([" + R1 + "] < 1, [" + R2 + "], "
                        +"con([" + R2 + "] < 1, [" + R1 + "], int(" + W1 + " * [" + R1 + "] + " + W2 + " * [" + R2 + "])" + "))))";